Changes made by Commission Regulation (EEC) No 1551/80 of 20 June 1980 amending for the sixth time Regulation (EEC) No 557/79 laying down detailed rules for the application of the system of consumption aid for olive oil and amending Regulation (EEC) No 2041/75 on special detailed rules for the application of the system of import and export licences and advance fixing certificates for oils and fats: Regulation (EEC) No 2041/75 of the Commission of 25 July 1975 on special detailed rules for the application of the system of import and export licences and advance fixing certificates for oils and fats