Commission Regulation (EEC) No 1521/78 of 30 June 1978 re-establishing the levying of the customs duties on other illuminating glassware, signalling glassware and optical elements of glass, not optically worked nor of optical glass, falling within subheading 70.14 B, originating in Hong Kong to which the preferential tariff arrangements set out in Council Regulation (EEC) No 2705/77 apply