Joined Cases C-346/03 and C-529/03: Judgment of the Court (Third Chamber) of 23 February 2006 (reference for a preliminary ruling from the Tribunale di Cagliari, Tribunale ordinario di Cagliari) — Giuseppe Atzeni, Francesco Atzori, Giuseppe Ignazio Boi v Regione autonoma della Sardegna (State aid — Decision 97/612/EC — Preferential loans in favour of agricultural undertakings — Article 92(2)(b) and (3)(a) and (c) of the EC Treaty (now, after amendment, Article 87(2)(b) and (3)(a) and (c) EC) — Admissibility — Legal basis — Legitimate expectations)