Article 22
The arbitral tribunal shall decide which further written statements, in addition to the statement of claim and the statement of defence, shall be required from the parties or may be presented by them and shall fix the periods of time for communicating such statements.

Periods of Time

Article 23
The periods of time fixed by the arbitral tribunal for the communication of written statements (including the statement of claim and statement of defence) should not exceed forty-five days. However, the arbitral tribunal may extend the time limit if it concludes that an extension is justified.

Evidence and Hearings (Articles 24 and 25)

Article 24
1. Each party shall have the burden of proving the facts relied on to support his claim or defence.