Case T-279/02: Judgment of the Court of First Instance of 5 April 2006 — Degussa v Commission (Competition — Article 81 EC — Cartels — Methionine market — Unique and continuous nature of the infringement — Fine — Guidelines for calculating the amount of fines — Gravity and duration of the infringement — Cooperation during the administrative procedure — Article 15(2) of Regulation No 17/62 — Presumption of innocence)