++++ 1 . Community law - Principles - Force majeure - Effects - Creation of rights not provided for by the rules - Precluded 2 . Agriculture - Common organization of the markets - Milk and milk products - Additional levy on milk - Determination of reference quantities exempt from the levy - Taking account of exceptional events which have affected production - Limits - Choice of a reference year outside the options offered by the Community rules - Precluded ( Council Regulation No 857/84, Art . 3 ( 3 ); Commission Regulation No 1371/84 ) 3 . Agriculture - common agricultural policy - Objectives - Rational development of milk production and guarantee of fair earnings for producers - Introduction of an additional levy on milk - Lawfulness ( EEC Treaty, Art . 39 ( 1 ) ( a ) and ( b ); Council Regulation No 857/84; Commission Regulation No 1371/84 ) 4 . Agriculture - Common organization of the markets - Milk and milk products - Additional levy on milk - Producers who are victims of exceptional events affecting their production throughout the reference period - Burden not disproportionate ( Council Regulation No 857/84; Commission Regulation No 1371/84 5 . Agriculture - Common organization of the markets - Discrimination between producers or consumers - Additional levy on milk - Different effects on producers according to their production during a reference period - No discrimination ( EEC Treaty, Art . 40 ( 3 ), second subparagraph; Council Regulation No 857/84; Commission Regulation No 1371/84 )