Changes made by 77/373/EEC: Commission Decision of 13 May 1977 excluding from admission free of Common Customs Tariff duties the scientific apparatus described as 'Precision Lock-in-Amplifier' , PAR, model 124 A with plug-in-preamplifier, PAR model 116
EU Decision 1977/373
No changes made by 77/373/EEC: Commission Decision of 13 May 1977 excluding from admission free of Common Customs Tariff duties the scientific apparatus described as 'Precision Lock-in-Amplifier' , PAR, model 124 A with plug-in-preamplifier, PAR model 116 are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.