JUDGMENT OF THE COURT (First Chamber) of 17 September 1997 in Case C-130/96 (reference for a preliminary ruling from the Supremo Tribunal Administrativo): Fazenda Pública v. Solisnor-Estaleiros Navais SA, also represented: Ministério Público (VAT - Article 33 of the sixth VAT Directive - Maintenance of stamp duties - Stamp duty on the value of contracts relating to the construction of an oil tanker)