Subsection 5.

Subsection 5. The composition of the Tribunal for particular cases
Article 16 

1. No Member who is a national of a party in a case, a national of a State member of an international organization which is a party in a case or a national of a sponsoring State of an entity other than a State which is a party in a case, shall exercise the functions of the presidency in respect of the case. 2. The Member who is presiding in a case on the date on which the Tribunal meets in accordance with article 68 shall continue to preside in that case until completion of the current phase of the case, notwithstanding the election in the meantime of a new President or Vice-President of the Tribunal. If he should become unable to act, the presidency for the case
shall be determined in accordance with article 13 and on the basis of the composition of the Tribunal on the date on which it met in accordance with article 68.
Article 17

Members who have been replaced following the expiration of their terms of office shall continue to sit in a case until the completion of any phase in respect of which the Tribunal has met in accordance with article 68.
Article 18

1. Whenever doubt arises on any point in article 8 of the Statute, the President of the Tribunal shall inform the other Members. The Member concerned shall be afforded an opportunity of furnishing any information or explanations. 2. If a party desires to bring to the attention of the Tribunal facts which it considers to be of possible relevance to the application of article 8 of the Statute, but which it believes may not be known to the Tribunal, that party shall communicate confidentially such facts to the President of the Tribunal in writing.
Article 19

1. If a party intends to choose a judge ad hoc in a case, it shall notify the Tribunal of its intention as soon as possible. It shall inform the Tribunal of the name, nationality and brief biographical details of the person chosen, preferably at the same time but in any event not
later than two months before the time-limit fixed for the filing of the counter-memorial. The judge ad hoc may be of a nationality other than that of the party which chooses him. 2. If a party proposes to abstain from choosing a judge ad hoc, on condition of a like abstention by the other party, it shall so notify the Tribunal, which shall inform the other party. If the other party thereafter gives notice of its intention to choose, or chooses, a judge ad hoc, the time-limit for the party which had previously abstained from choosing a judge may be extended up to 30 days by the President of the Tribunal. 3. A copy of any notification relating to the choice of a judge ad hoc shall be communicated by the Registrar to the other party, which shall be requested to furnish, within a time-limit not exceeding 30 days to be fixed by the President of the Tribunal, such observations as it may wish to make. If within the said time-limit no objection is raised by the other party, and if none appears to the Tribunal itself, the parties shall be so informed. In the event of any objection or doubt, the matter shall be decided by the Tribunal, if necessary after hearing the parties.  4. A judge ad hoc who becomes unable to sit may be replaced. 5. If the Tribunal finds that the reasons for the participation of a judge ad hoc no longer exist, that judge shall cease to sit on the bench.