Changes to 91/526/EEC: Commission Decision of 4 October 1991 suspending the buying-in of butter in certain Member States (Only the German, English, French and Dutch texts are authentic)
EU Decision 1991/526
No changes to 91/526/EEC: Commission Decision of 4 October 1991 suspending the buying-in of butter in certain Member States (Only the German, English, French and Dutch texts are authentic) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.