Changes made by 81/956/EEC: Fourth Council Decision of 16 November 1981 on the equivalence of seed potatoes produced in third countries
EU Decision 1981/956
No changes made by 81/956/EEC: Fourth Council Decision of 16 November 1981 on the equivalence of seed potatoes produced in third countries are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.