94/500/EC: Council Decision of 21 February 1994 concerning the conclusion of an Agreement in the form of an Exchange of Letters between the European Community and the Republic of Poland amending Annex IVb to the Interim Agreement between the European Coal and Steel Community and the European Economic Community, of the one part, and the Republic of Poland, of the other part, and to the Europe Agreement between the European Communities and their Member States, of the one part, and the Republic of Poland, of the other part