Changes made by Regulation (ECSC, EEC, Euratom) No 1543/73 of the Council of 4 June 1973 introducing special measures temporarily applicable to officials of the European Communities paid from research and investment funds
EU Regulation No 1543/1973
No changes made by Regulation (ECSC, EEC, Euratom) No 1543/73 of the Council of 4 June 1973 introducing special measures temporarily applicable to officials of the European Communities paid from research and investment funds are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.