Changes made by 91/28/EEC: Commission Decision of 19 December 1990 authorizing certain Member States to provide for exceptions from certain provisions of Directive 77/93/EEC in respect of potatoes for human consumption originating in Turkey (only the German, French and Dutch texts are authentic)
EU Decision 1991/28
No changes made by 91/28/EEC: Commission Decision of 19 December 1990 authorizing certain Member States to provide for exceptions from certain provisions of Directive 77/93/EEC in respect of potatoes for human consumption originating in Turkey (only the German, French and Dutch texts are authentic) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.