COMMISSION REGULATION (EC) No 829/95 of 12 April 1995 derogating from Commission Regulation (EC) No 1223/94 laying down special detailed rules for the application of the system of advance-fixing certificates for certain agricultural products exported in the form of goods not covered by Annex II to the Treaty, and derogating from Commission Regulation (EEC) No 3665/87 laying down common detailed rules for the application of the system of export refunds on agricultural products