1. In any proceedings before the Office, the means of giving or obtaining evidence may include the following:
(a) hearing the parties to proceedings;
(b) requests for information;
(c) the production of documents or other evidence;
(d) hearing the witnesses;
(e) opinions by experts;
(g) sworn affidavits.
2. Where the Office decides through a collective body, that body may commission one of its members to examine the evidence adduced.
3. If the Office considers it necessary that a party to proceedings, witness or expert give evidence orally, it shall either:
(a) issue a summons requiring the relevant person to appear before it; or
(b) request the competent judicial or other authority in the country of domicile of the relevant person to take the evidence as provided for in Article 91 (2).
4. A party to proceedings, witness or expert who is summoned before the Office may request it to allow his evidence to be heard by the competent judicial or other authority in his country of domicile. On receipt of such a request or in the case that no reaction was given to the summons, the Office may, in accordance with Article 91 (2), request the competent judicial or other authority to hear the evidence of that person.
5. If a party to proceedings, witness or expert gives evidence before the Office, the Office may, if it considers it advisable that the evidence be given under oath or otherwise in binding form, request the competent judicial or other authority in the country of domicile of the relevant person to hear his evidence under the requisite conditions.
6. When the Office requests a competent judicial or other authority to take evidence, it may request it to take the evidence in binding form and to permit a member of the Office to attend the hearing and question the party to proceedings, witness or expert either through that judicial or other authority or directly.