1. The arbitral tribunal shall apply the rules of law designated by the parties as applicable to the substance of the dispute. Failing such designation by the parties, the arbitral tribunal shall apply the law which it determines to be appropriate.

2. The arbitral tribunal shall decide as amiable compositeur or ex aequo et bono only if the parties have expressly authorized the arbitral tribunal to do so.

3. In all cases, the arbitral tribunal shall decide in accordance with the terms of the contract, if any, and shall take into account any usage of trade applicable to the transaction.