2. a) Si les Parties s'y refusent, il est procédé, à la demande d'au moins l'une des Parties, à la constitution d'un Comité d'arbitres. Le Comité sera constitué, autant que possible, par l'accord des Parties. {135} with one another or against a State which, if the occasion arises accepts all the obligations hereinafter set out, except in case of resistance to acts of aggression or when acting in agreement with the Council or the Assembly of the League of Nations in accordance with the provisions of the Covenant and of the present Protocol. ARTICLE 3. The signatory States undertake to recognise as compulsory, _ipso facto_ and without special agreement, the jurisdiction of the Permanent Court of International Justice in the cases covered by paragraph 2 of Article 36 of the Statute of the Court, but without prejudice to the right of any State, when acceding to the special protocol provided for in the said Article and opened for signature on December 16th, 1920, to make reservations compatible with the said clause. Accession to this special protocol, opened for signature on December 16th, 1920, must be given within the month following the coming into force of the present Protocol. States which accede to the present Protocol, after its coming into force, must carry out the above obligation, within the month following their accession. ARTICLE 4. With a view to render more complete the provisions of paragraphs 4, 5, 6, and 7 of Article 15 of the Covenant, the signatory States agree to comply with the following procedure: 1. If the dispute submitted to the Council is not settled by it as provided in paragraph 3 of the said Article 15, the Council shall endeavour to persuade the parties to submit the dispute to judicial settlement or arbitration. 2. (_a_) If the parties cannot agree to do so, there shall, at the request of at least one of the parties, be constituted a Committee of Arbitrators. The Committee shall so far as possible be constituted by agreement between the parties. {136} _b_) Si, dans le délai que le Conseil aura fixé, elles ne se sont pas entendues en tout ou en partie sur le nombre, le nom et les pouvoirs des arbitres, ainsi que sur la procedure, le Conseil réglera les points en suspens. Il choisira d'urgence--en consultant les Parties--les arbitres et leur président, parmi les personnes qui, par leur nationalité, leur caractère et leur expérience, lui paraîtront donner les plus hautes garanties de compétence et d'impartialité. _c_) Après que les conclusions des Parties auront été formulées, le Comité d'arbitres, à la demande de toute Partie, sollicitera, par l'entremise du Conseil, sur les points de droit contestés, l'avis consultatif de la Cour permanente de Justice Internationale qui, dans ce cas, se réunira d'urgence.