Arbitration — The award — Appeal and revision — Appeal against judgment on merits — Whether tribunal competent to reconsider question of admissibility of original appeal at this stage — Appeal to Plenary Session of Arbitral Commission on Property, Rights and Interests in Germany — Decision on admissibility given previously by Chamber of Commission — Enforceability of award — Competence of Commission to declare its awards enforceable — Basis of competence of Arbitral Commission.