Edited by Jürgen Basedow, Giesela Rühl, Franco Ferrari and Pedro de Miguel Asensio
Chapter M.9: Money and currency
1. In general
Despite difficulties of definition, the terms ‘money’ and ‘currency’ should be distinguished, in that money (argent, Geld, dinero) is an abstract concept denoting possession of purchasing power, whereas currency (monnaie, Währung, moneda) denotes a concrete means of exchange, issued by a state which uses it as the blood of the economy. Seen in this way, the concept of money is broader than that of currency. It has been stated that ‘Money is a term so frequently used and of such importance that one is apt to overlook its inherent difficulties, and to forget that the multitude of its functions necessarily connotes a multitude of meanings in different legal situations’ (Charles Proctor, Mann on the Legal Aspects of Money (7th edn, OUP 2012) N.1.01). In other words, it is necessary to look at the functions fulfilled by money to define it as a legal concept.
The concept of money may be reduced to three different functions: (i) a unit designed to measure value characterized by a specific name (the abstract aspect of money), as well as (ii) the representation of purchasing power and (iii) a means of payment, both of which represent the concrete aspect money (Stephen A Silard, ‘Money and Foreign Exchange’, International Encyclopedia of Comparative Law XXVIII (1975) ch 20, 20–22).
2. Money in public international law
Money in public international law is described as a part of the sovereign monetary power of the state. The state’s sovereign power to define its own currency was first recognized in England (Emperor of Austria v Day and Kossuth  3 DeG F&J 217), when Lord Justice Turner stated
[t]he regulation of the coin and currency of every State is a great prerogative right of the sovereign power . . . Money is the medium of commerce between all civilized nations; therefore the prerogative of each sovereign State as to money is but a great public right recognized and protected by the law of nations.
The PCIJ affirmed this view in the Serbian and Brazilian loans cases in 1929 (Case concerning the Payment of various Serbian Loans issued in France/Case concerning the Payment in Gold of the Brazilian Federal Loans issued in France, PCIJ series A Nos 20/21). The Swiss Private International Law Act (Bundesgesetz über das Internationale Privatrecht of 18 December 1987, 1988 BBl I 5, as amended, henceforth Swiss PILA) has enshrined this principle in art 147(1): ‘Currency is defined by the law of the State issuing the currency’. This internal aspect of monetary sovereignty has been perpetuated in the creation of the Euro, in that those EU Member States within the euro zone have remitted their sovereign monetary power to the EU, which accordingly has exclusive competence over monetary policy in those states (art 3 TFEU (The Treaty on the Functioning of the European Union (consolidated version),  OJ C 326/47)). Meanwhile, the German Federal Constitutional Court has confirmed that this transfer of competence was compatible with the German Constitution (Grundgesetz für die Bundesrepublik Deutschland, 23 May 1949, BGBl. p 1) in the Maastricht Judgment of 12 October 1993 (Federal Constitutional Court of Germany (BVerfG), 89 BVerfGE 155).
Monetary sovereignty also exhibits an external character, in that external monetary sovereignty entitles the state to impose its own statutory system of exchange control to protect its currency vis-à-vis other states. However, for States Party to the IMF, the Bretton Woods Agreement (Articles of Agreement of 27 December 1945 of the p. 1256International Monetary Fund, adopted in Bretton Woods on 22 July 1944, 2 UNTS 39) restricts that protective right through an international exchange control system, although rather than prohibiting national exchange control statutes, the Agreement sets strict legal requirements for them.
3. Private international law
From a private international law perspective, money should be studied both as a unit of value (currency of account) and a means of payment (currency of payment). The use of a foreign currency (ie a currency which is not the one of the forum) entails questions of applicable law, jurisdiction and enforcement of foreign decisions.
II. Historical development
1. The gold era
The existence of metallic coins circulating as means of payment is as ancient as the first codification of law. A reference to metallic coins is found in the Hammurabi Code (around 1760 BC). For centuries, currencies were defined with reference to a certain weight of silver and/or gold. Each country decided for itself the definition of its currency, without regard to the definition of other currencies. Monetary legislation existed only at the national level. At the end of the 19th century, gold became the common reference for national currencies. Countries which previously had adopted a bimetallism definition of their currencies, using gold and silver, waived their reference to silver. Within such a system, the exchange rate between currencies was fixed, the common denomination being gold.
However, the ‘gold standard’ was abandoned after the First World War, because the system could not meet the monetary needs of reconstruction and payment of war reparation debts. In its place came the ‘gold exchange standard’, whereby central bank reserves could be made not only in gold but also in currencies exchangeable for gold (mainly the US dollar and the pound sterling) (Benvenuto Griziotti, ‘L’évolution monétaire dans le monde depuis la guerre de 1914’ (1934) 49 Rec. des Cours 70). These measures were accompanied by national legislation prohibiting payment in gold, in order to protect national gold reserves. At the same time, in the 1920s the first international conventions were concluded between states and the League of Nations in order to save the currencies of European states (Boris Nolde, ‘La monnaie en droit international public’ (1929) 27 Rec. des Cours 322). This regime of fixed exchange rates, based upon a ratio between currencies and gold and dependant solely on the will of governments, disappeared after the Second World War.
2. The Bretton Woods system
After the period before the Second World War of national currency instability in Europe, an agreement was reached in July 1944 to establish an international monetary system which would promote currency stability through fixed rates of exchange. The Bretton Woods agreements became effective on 27 December 1945. A par value was fixed in terms of gold as the common denominator of the par value system. A par value could be expressed directly in terms of gold of the weight and fineness in effect on 1 July 1944, or indirectly in relation to the US dollar. Consultation with the Fund was necessary before a member made any alteration to its par value. Most countries opted for the second indirect (dollar-based) option, with the result in effect that the common denominator of monetary systems shifted from gold to the US dollar. During the subsequent two-and-a-half decades, national currencies benefitted from a remarkable degree of stability, allowing international trade to flourish.
3. The post-Bretton Woods system
The period of post-war stability ended in 1971, when the then President of the United States, Richard Nixon, decided on 15 August that the USA would no longer undertake to maintain a specific external value for the US dollar. Since then the international monetary system has undergone radical changes. The 1971 decision led to the Second Amendment of the IMF Articles of Agreement on 30 April 1976, which became effective on 1 April 1978 (15 ILM 546). This amendment abandoned the fixed exchange rate system, and allowed national currencies to fluctuate. State members were then free to choose their exchange rate regime, subject to one exception of the prohibition against maintaining the external value of their currencies p. 1257in terms of gold. Basically, three exchange rate regimes may be distinguished: (i) what economists call ‘hard peg’, where a state introduces the currency of a more developed country rather than having an own currency (phenomenon of ‘dollarization’), (ii) ‘soft peg’ (or intermediate) where a state pegs its own currency to the currency of a more developed country (or to a composite of currencies) and (iii) the floating exchange rate, where countries decide not to interfere with market forces and leave the exchange rate to the interaction of supply and demand.
III. Legal sources
Very few European countries have adopted private international law rules on money or currency. Noteworthy exceptions are the Swiss PILA, art 147 of which addresses currency issues in private international law, and the Romanian Civil Code (Law 287/2009, published in the Official Gazette No 511 of 24 July 2009, and subsequently amended and supplemented by Law 71/2011, published in the Official Gazette No 409 of 10 June 2011), whose provisions on private international law (Book 7) contain art 2.646 on the currency of payment, a provision similar to art 147 Swiss PILA. The Polish Private International Law Act (Official Journal 2011 No 80, pos. 432, henceforth Polish PILA) also contains an article on currency (art 38).
As far as substantive rules on currency or monetary obligations are concerned, some legal systems contain specific rules on the payment of monetary obligations and usually offer the possibility to the debtor to perform its obligation by paying with the local currency, ie the currency of the state where the payment shall take place (see for instance § 244 German Civil Code (Bürgerliches Gesetzbuch of 2 January 2002, BGBl. I 42, as amended); art 1277 ff Italian Civil Code (Codice Civile, Gazz.Uff. 4 April 1942, No 79 and 79bis; edizione straordinaria) and art 84 Swiss Code of Obligations (Bundesgesetz betreffend die Ergänzung des Schweizerischen Zivilgesetzbuches (Fünfter Teil: Obligationenrecht) of 14 June 1881, SR 220)). The French Monetary and Financial Code (Code monétaire et financier, 2000 (available at <www.legifrance.gouv.fr>)) seems to be the sole piece of codification on monetary legislation in Europe. The first book is dedicated to the law of currency.
The Articles of Agreement of the International Monetary Fund are the central legal instrument of the international monetary system and of international monetary law.
The euro is regulated by various European texts. Among the most important are Regulations 1103/97 (Regulation (EC) No1103/1997 of the European Council of 17 June 1997 on certain provisions relating to the introduction of the euro,  OJ L 162/1) and 974/98 (Regulation (EC) No 974/1998 of the European Council of 3 May 1998 on the introduction of the euro,  OJ L 139/1), which created the euro, while Regulation 260/2012 (Regulation (EU) No 260/2012 of the European Parliament and of the Council of 14 March 2012 establishing technical and business requirements for credit transfers and direct debits in euro and amending Regulation (EC) No 924/2009,  OJ L 94/22) regulates credit transfers and direct debits in euro.
There are no specific texts on the conflict of laws on monetary obligations in the EU. However, art 12 Rome I Regulation (Regulation (EC) No 593/2008 of the European Parliament and of the Council of 17 June 2008 on the law applicable to contractual obligations (Rome I),  OJ L 177/6; →Rome Convention and Rome I Regulation) and art 15 Rome II Regulation (Regulation (EC) No 864/2007 of the European Parliament and of the Council of 11 July 2007 on the law applicable to non-contractual obligations (Rome II),  OJ L 199/40) address the law to be taken into consideration for payment. Incidentally, a European Convention on Foreign Money Liabilities (60 ETS) was adopted on 11 December 1967 in Paris. Four Member States of the European Council signed it but only Luxembourg ratified it, so that the Convention has never entered into force.
IV. Current issues implying the use of foreign currency in private international relationships
1. Determination of the currency of account in a contractual relationship
Most legal systems provide that, in case of an absent or ambiguous currency denomination, the determination of the currency of account is p. 1258a question of interpretation to be solved by the lex causae. Thus, the designation of the currency of account is a two-step process. First, it is necessary to determine the legal system governing the construction of the contract. Second, the domestic rules of the applicable law will be used to ascertain the currency of account (Charles Proctor, Mann on the Legal Aspects of Money (7th edn, OUP 2012) N. 5.08; Albert Venn Dicey, John Humphrey Carlile Morris and Lawrence Collins (eds), Dicey, Morris and Collins on the Conflict of Laws (14th edn, Sweet & Maxwell 2006) rule 209: ‘Where there is doubt as to the currency in which a debt is expressed (money of account), and especially where the expression used for the denomination thereof connotes the currencies of two or more States . . . the money of account must be ascertained by construing the contract in accordance with the law applicable to it’). In case of →damages, a more direct rule might be used to designate the most relevant currency to be used for the assessment of damages, without having regard to a specific applicable law but by using a →connecting factor (the habitual residence of the creditor) (Caroline Kleiner, La monnaie dans les relations privées internationales (LGDJ 2010) 218). This connecting factor method is used in the UNIDROIT Principles (International Institute for the Unification of Private Law/Institut international pour l’unification du droit privé (ed), UNIDROIT Principles of International Commercial Contracts 2010 (3rd edn, UNIDROIT 2010)). Article 7.4.12 states that ‘damages are to be assessed either in the currency in which the monetary obligation was expressed or in the currency in which the harm was suffered, whichever is more appropriate’. The same method has also been applied in various court decisions in →France, Scotland and →Germany concerning the choice of currency of account of damages (Oliver Remien, ‘Schadensersatzwährung im Deliktrecht’  ZEuP 119).
2. Debt labelled in foreign unit of account
Contracting parties may agree to assess their obligations in a currency of account which is neither the one used in their domicile state, nor that of the state of the place of payment, nor that of the state whose law governs their contract. Instead parties use a foreign unit of account. Whether that choice is permitted depends on the law applicable to the contract, as it is an issue pertaining to the determination of the obligation itself. However, not all European legal systems follow this approach. For example, according to French case-law, monetary clauses included in international contracts, defined as contracts implying a movement of monetary flow from and into the country, are valid, notwithstanding their invalidity according to the lex contractus (Cass. civ., 21 June 1950, Messageries maritimes, Bertrand Ancel and Yves Lequette, in Les grands arrêts de la jurisprudence française de droit international privé (5th edn, Dalloz 2006) N.22).
If such choice of currency is lawful, then the issue arises of the value of the chosen currency. This in turn raises the issue of whether the ‘nominalism’ principle should be applied. Some scholars argue that the nominalism principle applies as a principle of international law, regardless of the applicable law (Frederick Alexander Mann, ‘Money in Public International Law’ (1959) 96 Rec. des Cours 1, 106–8 and 115–17; Dominique Carreau, Souveraineté et coopération monétaire (Julliard 1974) 62). However, the predominant approach consists in regarding nominalism as an implicit term of a contract. Consequently, when parties omit to safeguard themselves by appropriate protective clauses, they must be considered to have accepted the risks of depreciation of the monetary unit they have chosen for their relations. According to this view, application of the nominalism principle should be governed by the proper law of the contract or the law applicable to the relationship to which the monetary obligation is attached. English scholars have thus formulated the following rule:
In whatever currency a debt is expressed, it is for the law governing the transaction from which the debt arises, eg in the case of a contractual debt for the law applicable to the contract, to determine whether and to what extent the debtor is liable, in the event of a depreciation of the currency, to make additional payment to the creditor by way of revalorization. (Albert Venn Dicey, John Humphrey Carlile Morris and Lawrence Collins (eds), Dicey, Morris and Collins on the Conflict of Laws (14th edn, Sweet & Maxwell 2006) rule 207, No. 36-015)
The same rule is enshrined in art 147(2) Swiss PILA, which states that ‘the effect that currency exerts on the amount of a debt shall be governed by the law applicable to the debt’, as p. 1259well as in art 2.646(2) Romanian Civil Code and art 38 Polish PILA. However, this solution ignores the principle that only the issuing state is empowered to define the value of its currency, according to the lex monetae principle. In other words, the value of a currency and its effects on the obligation depends on the law of the state which enacted that currency (Helmut Grothe, Fremdwährungsverbindlichkeiten, das Recht der Geldschulden mit Auslandsberührung Kollisionsrecht – Materielles Recht – Verfahrensrecht (Walter de Gruyter 1999) 158; Tullio Treves, ‘Les effets de la dépreciation monétaire sur les rapports juridiques contractuels en droit international privé italien’ in Les effets de la dépréciation monétaire sur les rapports juridiques contractuels, Travaux de l’association Henri Capitant, tome XXIII Journées d’Istambul (Economica 1973) 213, 215 and 221).
3. Payment of a debt with a foreign currency
The distinction between currency of account and currency of payment includes the assumption that, although a monetary obligation is assessed in a particular currency, payment will not necessarily be made in that specific currency. Parties may have agreed that the payment of their contractual obligation should be paid in another currency than that they have chosen for their obligation. Absent an express choice, it is necessary to determine the currency of payment and whether payment in a foreign currency is valid. Both questions raise private international law issues, since the payment in a foreign currency implies the application of at least one foreign legal system, that of the currency of payment, the lex monetae.
Determination of the currency of payment and whether an obligation may be discharged by payment in a foreign currency may depend on different legal systems. First, as these questions concern the performance of an obligation, they should probably be governed by the lex causae. However, art 10(2) Rome Convention (Rome Convention on the law applicable to contractual obligations (consolidated version),  OJ C 27/34) as well as art 12(2) Rome I Regulation provide that ‘in relation to the manner of performance and the steps to be taken in the event of defective performance, regard shall be had to the law of the country in which performance takes place’. According to this provision, the law of the country where payment is to be made (the lex loci solutionis) will be taken into account, the manner of performance being understood by the Convention drafters as encompassing determination of the currency of payment (Mario Giuliano and Paul Lagarde, ‘Report on the Convention on the law applicable to contractual obligations by Mario Giuliano, Professor, University of Milan, and Paul Lagarde, Professor, University of Paris I’  OJ C 282/1, 33). The same solution, but framed in clearer words, has been adopted in Switzerland. Article 147(3) Swiss PILA provides that ‘[t]he law of the State in which payment must be made shall determine in which currency the payment is to be made’. In the same vein, art 2.646(3) Romanian Civil Code provides that ‘the law of the State in which payment must be made shall determine in which currency the payment is to be made, unless the parties, in the private international law relationships resulting from the contract, have agreed on another currency of payment’. At first sight, the solution is simple. However, when the parties omit to determine the place of payment, the lex loci solutionis will depend on the designation of the place of payment, which depends in turn on the lex causae according to the ECJ (Case 12/76 Industrie Tessili Italiana Como v Dunlop AG  ECR 1473).
Certain legal systems provide for substantive rules related to the currency of payment in case of a local payment. In Germany, § 244 Civil Code offers the debtor the possibility to discharge its obligation in local currency (in euro) when the debt is payable within the country, unless payment in another currency has been expressly agreed (Helmut Grothe, Fremdwährungsverbindlichkeiten, das Recht der Geldschulden mit Auslandsberührung Kollisionsrecht – Materielles Recht – Verfahrensrecht (Walter de Gruyter 1999) 131). Similarly, art 84 Swiss Code of Obligations provides that the debtor may offer a payment in Swiss francs if the payment takes place in Switzerland, but only if parties had not foreseen a compulsory payment in the agreed currency of payment. The UNIDROIT Principles lay down the same rule in art 6.1.9, but add more precise rules applicable where the currency of payment cannot be obtained because of its inconvertibility. The article also stipulates that
the payment in the currency of the place for payment is to be made according to the applicable p. 1260rate of exchange prevailing there when payment is due. However, if the obligor has not paid at the time when payment is due, the obligee may require payment according to the applicable rate of exchange prevailing either when payment is due or at the time of actual payment.
In France, the seminal distinction is that drawn between domestic and international contracts. With domestic contracts, payment made in France should always be made in the French currency, whereas payment in international contracts should be discharged in the agreed currency (art. 1343-3 of the French civil code).
In Germany, there is a debate on whether such substantive rules should be applied as part of the lex causae or as lois d’application immediate. For the lex causae it is argued that since choice of the currency of payment is a party right, § 244 German Civil Code should be applied only when German law governs the contract (Helmut Grothe, Fremdwährungsverbindlichkeiten, das Recht der Geldschulden mit Auslandsberührung Kollisionsrecht – Materielles Recht – Verfahrensrecht (Walter de Gruyter 1999) 131). But other scholars argue that this stipulation applies whenever payment is due in Germany, whatever the applicable law (Karsten Schmidt, ‘§ 244 BGB’ in Christian Baldus and others (eds), J. von Staudingers Kommentar zum Bürgerlichen Gesetzbuch (Sellier-de Gruyter 1997) para 77; Georg Maier-Reimer, ‘Fremdwährungsverbindlichkeiten’  NJW 2049). In Switzerland, the rationale for application of art 84 Code of Obligations has led to no such doctrinal split, so that art 84 is considered applicable whenever a payment is to be discharged in Switzerland, irrespective of whether Swiss law is the lex contractus (Denis Loertscher, Commentaire Romand, Code des obligations I (2nd edn, Helbing & Lichtenhahn 2012) art 84, para 14).
4. Judgment or arbitral award in foreign currency
Municipal courts are confronted with the problem of designation of the unit of account only where they have the right to choose the money of account in their judgment. That is to say, the issue arises only when courts are not compelled to use the monetary unit of the forum (the so-called moneta fori). Whether a foreign unit of account may be used is a procedural issue, which should therefore be governed by procedural law, ie the →lex fori. The current state of law in most countries is that municipal courts enjoy a degree of liberty to render their judgments in a foreign currency. However, in England, the law changed with the Milangos case (Miliangos v George Frank Ltd  AC 443; Vaughan Black, Foreign Currency Claims in the Conflict of Laws (Hart Publishing 2010) 25). In France, courts may assess the damages awarded in a foreign currency since the 1920s (Caroline Kleiner, La monnaie dans les relations privées internationales (LGDJ 2010) 197). In the →USA, the Restatement (Third) on Foreign relations (American Law Institute, Restatement of the Law, Third: The Foreign Relations Law of the United States, St. Paul 1987) suggests in its § 823 (Judgments on Obligations in Foreign Currency: Law of the United States) that US courts ordinarily give judgment on causes of action arising in another state, or denominated in a foreign currency, in US dollars. However, they are not precluded from giving judgment in the currency in which the obligation is denominated or the loss was incurred.
The situation is different for choice of currency in arbitral awards. Arbitrators have no forum and are bound only by party autonomy, so that arbitration laws are generally silent on the currency issue. An exception is art 48(4) English Arbitration Act 1996 (ch 23), which provides that ‘[t]he tribunal may order the payment of a sum of money, in any currency’. This freedom of choice entails that the currency of account should be determined according to a specific method, either by referring to the lex causae (traditional approach) or to a direct method using a connecting factor (see IV.1.).
5. Recognition of foreign judgment labelled in a foreign currency
When enforcement of a judgment is sought abroad, the issue arises of whether the national court where enforcement is sought can adjust the quantum of →damages awarded to take into account any depreciation of the currency used in the judgment. To re-evaluate the quantum awarded by a foreign court clearly conflicts with the principle denying substantive review of judgments. Where a foreign judgment requires a party to pay a certain amount of damages expressed in a foreign currency, French case-law refuses to reassess the quantum of damages, even when the currency has been devalued p. 1261(Cass civ (1), 11 June 2002, Molinari, Rev.crit.DIP 2003, 318, with observations by Horatia Muir Watt).
Whenever damages in a judgment are expressed in a foreign currency, be it a local or a foreign judgment to be enforced, the enforcement needs to go through a conversion process. Indeed, most countries apply the rule that enforcement of judicial decisions should be discharged in local currency (Frank Vischer, Geld- und Währungsrecht im nationalen und internationalen Kontext (Helbing Lichtenhahn 2010) 30). Consequently, the debt must be converted into the local currency at the rate of exchange on the day of payment. Thus the Restatement (Second) on Conflict of Laws (American Law Institute, Restatement of the Law, Second: Conflict of Laws 2d, St. Paul 1971; →Restatement (First and Second) of Conflict of Laws) suggests in § 144 that when enforcement of a foreign judgment expressed in foreign currency is sought in the USA, ‘the forum will convert the currency as of the date of the award’.
6. Exchange control provisions
Exchange control regulations are intended to safeguard a country’s balance of payments (George Van Hecke, ‘Currency’, International Encyclopedia of Comparative Law III (1972) ch 36, 36 N.15). The adoption of such measures is subject to certain conditions for states that are parties to the IMF (see I.2.). When Member States comply with the IMF Agreement requirements, their exchange control regulations are granted recognition in other member countries according to art VIII-2 b) of the Agreement, which states that ‘[e]xchange contracts which involve the currency of any member and which are contrary to the exchange control regulations of that member maintained or imposed consistently with this Agreement, shall be unenforceable in the territories of any member’. An authoritative interpretation of art VIII-2 b) was delivered by the Fund’s Board of Executive Directors on 14 June 1949, according to which the prohibition of enforcement means that ‘the obligations of such contracts will not be implemented by the judicial or administrative authorities of member countries, for example, by decreeing performance of the contracts or by awarding damages for non-performance’.
V. Modern trends
The legal concept of money has been consistently challenged since the creation of so called ‘private money’, such as the bitcoin in 2008. What is challenged is the state monopoly over the creation of a monetary unit. From a legal point of view, this phenomenon cannot be qualified as money, since the essence of money is to permit and facilitate exchanges. Hence an instrument may be qualified as money only to the extent it is an officially accepted media for exchanges. In other terms, ‘money is that which serves as a means of exchange – subject to the crucial proviso that its functions must have the formal and mandatory backing of the domestic legal system in the State or area in which it circulates’ (Charles Proctor, Mann on the Legal Aspects of Money (7th edn, OUP 2012) N1.15). So far, no monetary legislation applies to relationships labelled in bitcoins. However, the ECJ decided that exchanges of traditional currencies for units of the "bitcoin" virtual currency and vice and versa constitute the supply of services exempted from VAT since they concern transactions concerning currency, bank notes and coins used as legal tender (ECJ, C-264/14, Skatteverket v. David Hedqvist). In a few states, specific legislation has been drafted and adopted to regulate the use of bitcoins in payments, which shows that they do not fit in the existing legislation. Bitcoins cannot be compared with other currencies, whose use requires no specific legislation.
Vaughan Black, Foreign Currency Claims in the Conflict of Laws (Hart Publishing 2010);
Geneviève Burdeau, ‘L’exercice des competences monétaires par les Etats’ (1988) 212 Rec. des Cours 211;
Dominique Carreau, ‘Le système monétaire international privé (UEM et Euromarchés)’ (1998) 274 Rec. des Cours 311;
François Gianviti, ‘Réflexions sur l’art VIII, section 2 b des Statuts du FMI’  Rev.crit.DIP 471;
Helmut Grothe, Fremdwährungsverbindlichkeiten, das Recht der Geldschulden mit Auslandsberührung Kollisionsrecht – Materielles Recht – Verfahrensrecht (Walter de Gruyter 1999);
Hugo J Hahn and Ulrich Häde, Währungsrecht (CH Beck 2010);
George Van Hecke, ‘Currency’, International Encyclopedia of Comparative Law III (1972) ch 36; Hideki Kanda and Kazuaki Sono, ‘The Future of Lex Monetae’ in Mario Giovanoli p. 1262and Diego Devos (eds), International Monetary and Financial Law: The Global Crisis (OUP 2011) 506;
Frédéric-Edouard Klein, ‘De l’application de l’Article VIII 2 (b) des Statuts du Fonds Monétaire International en Suisse’ in Christian Dominicé, Robert Patry and Claude Reymond (eds), Études de droit international en l’honneur de Pierre Lalive (Helbing & Lichtenhahn 1993) 261;
Caroline Kleiner, ‘Money in Private International Law: What Are the Problems? What Are the Solutions?’  YbPIL 565;
Caroline Kleiner, La monnaie dans les relations privées internationales (LGDJ 2010);
Elias Krispis, ‘Money in Private International Law’ (1967) 120 Rec. des Cours 191;
Denis Loertscher, Commentaire Romand, Code des obligations I (2nd edn, Helbing & Lichtenhahn 2012);
Georg Maier-Reimer, ‘Fremdwährungsverbindlichkeiten’  NJW 2049;
Frederick Alexander Mann ‘Money in Public International Law’ (1959) 96 Rec. des Cours 1;
Charles Proctor, Mann on the Legal Aspects of Money (7th edn, OUP 2012);
Luca Radicati di Brozolo, ‘International Payments and Conflicts of Laws’ (2000) 48 Am.J.Comp.L. 307;
Oliver Remien, ‘Schadensersatzwährung im Deliktrecht’  ZEuP 119;
Karsten Schmidt, ‘§ 244 BGB’ in Christian Baldus and others (eds), J. von Staudingers Kommentar zum Bürgerlichen Gesetzbuch (Sellier-de Gruyter 1997);
Karsten Schmidt, ‘Schuldwährung, Zahlungwährung und Zahlungsort. Eine Skizze zu Art. 84 OR, § 361 HGB und §§ 244, 270 BGB’ in Heinrich Honsell (ed), Privatrecht und Methode Festschrift für Ernst A. Kramer (Helbing & Lichtenhahn 2004) 684;
Stephen A Silard, ‘Money and Foreign Exchange’, International Encyclopedia of Comparative Law XXVIII (1975) ch 20; Tullio Treves, ‘Les effets de la dépreciation monétaire sur les rapports juridiques contractuels en droit international privé italien’ in Les effets de la dépréciation monétaire sur les rapports juridiques contractuels, Travaux de l’association Henri Capitant, tome XXIII Journées d’Istambul (Economica 1973) 213;
Frank Vischer, Geld- und Währungsrecht im nationalen und internationalen Kontext (Helbing Lichtenhahn 2010).