Changes made by 84/20/EEC: Commission Decision of 22 December 1983 authorizing the United Kingdom to restrict the marketing of seed of certain varieties of agricultural plant species (Only the English text is authentic)
EU Decision 1984/20
No changes made by 84/20/EEC: Commission Decision of 22 December 1983 authorizing the United Kingdom to restrict the marketing of seed of certain varieties of agricultural plant species (Only the English text is authentic) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.