++++ 1 . Agriculture - Common organization of the markets - Cereals - Co-responsibility levy - Legal basis ( EEC Treaty, Arts 39, 40 and 43; Council Regulation No 2727/75, Art . 4 ( 4 ), as amended by Regulation No 1579/86 ) 2 . European Communities' own resources - Article 201 of the Treaty - Scope - Charges levied in an agricultural sector to finance expenditure in that sector - Exclusion - Council Decision of 21 April 1970 - Scope ( EEC Treaty, Art . 201; Council Decision of 21 April 1970, Art . 2, second paragraph ) 3 . Community law - Principles - Fundamental rights - Right to property - Freedom to pursue a trade or profession - Restrictions - Permissibility - Conditions - Co-responsibility levy in the cereals sector - Permissibility 4 . Community law - Principles - Proportionality - Measures imposing financial charges - Proportionate nature - Criteria - Discretion of the Community legislature regarding the common agricultural policy - Review by the Court - Limits ( EEC Treaty, Arts 40 and 43 ) 5 . Agriculture - Common organization of the markets - Cereals - Co-responsibility levy - Measure appropriate to the operation of the common organization - Breach of the principle of proportionality - No ( EEC Treaty, Art . 39 ( 1 ) ( c ); Council Regulation No 2727/75, Art . 4, as amended by Regulation No 1579/86 ) 6 . Agriculture - Common organization of the markets - Discrimination between producers or consumers - Co-responsibility levy in the cereals sector - Exemption for products used after processing in the producer' s holding - Grant conditional on processing in the holding - Unlawful - Effects - Provisional maintenance of the rules in question on a non-discriminatory basis ( EEC Treaty, Art . 40 ( 3 ), second subparagraph, and Art . 177; Commission Regulation No 2040/86, Art . 1 ( 2 ), second subparagraph, as amended by Regulation No 2572/86 )