DECISION NO. 2007/019/R OF THE EXECUTIVE DIRECTOR OF THE EUROPEAN AVIATION SAFETY AGENCY OF 19 DECEMBER 2007 AMENDING DECISION NO 2003/12/RM OF THE EXECUTIVE DIRECTOR OF THE AGENCY OF 05 NOVEMBER 2003 ON GENERAL ACCEPTABLE MEANS OF COMPLIANCE FOR AIRWORTHINESS OF PRODUCTS, PARTS AND APPLIANCES («AMC-20»)