17The fixing of the common seal of the Crown Agents shall be authenticated by the signature of their secretary or some other person authorised by them to act for that purpose.
18(1)A document purporting to be duly executed under the seal of the Crown Agents shall be received in evidence and shall, unless the contrary is proved, be deemed to be so executed.
(2)A document purporting to be signed on behalf of the Crown Agents shall be received in evidence and shall, unless the contrary is proved, be deemed to be so signed.