Judgment of the Court (Second Chamber) of 1 July 2004 in Case C-295/02 (reference for a preliminary ruling from the Niedersächsisches Oberverwaltungsgericht): Gisela Gerken v Amt für Agrarstruktur Verden (Common agricultural policy — Integrated administration and control system for certain Community aid schemes — Regulations (EEC) No 3887/92 and (EC) No 2419/2001 — Applications for ‘livestock’ aid — Irregularities — Reduction in the amount of aid — Article 2(2) of Regulation (EC, Euratom) No 2988/95 — Retroactive application of a less stringent provision)