Changes made by Council Directive of 21 December 1977 on the approximation of the laws of the Member States relating to the defrosting and demisting systems of glazed surfaces of motor vehicles (78/317/EEC)
EU Directive 1978/317
No changes made by Council Directive of 21 December 1977 on the approximation of the laws of the Member States relating to the defrosting and demisting systems of glazed surfaces of motor vehicles (78/317/EEC) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.