unit of account used by the European Monetary Cooperation Fund, the Fund's operations in the currencies of the Member States shall be expressed in a European monetary unit of account of a value of 0.788867088 grams of fine gold, instrument de reglement definitif des relations monetaires entre les banques centrales des Etats membres de la Communaute, d'une part, et entre les banques centrales et le FECOM d'autre part