Changes to Council Directive 74/63/EEC of 17 December 1973 on the fixing of maximum permitted levels for undesirable substances and products in feedingstuffs
EU Directive 1974/63
Made by Commission Directive 97/8/EC of 7 February 1997 amending Council Directive 74/63/EEC on undesirable substances and products in animal nutrition
From legislation.gov.uk's record of changes, the official one: see it there.