13. A document purporting to be duly executed under the common seal of the[F2 Executive] shall be received in evidence and shall, unless the contrary is proved, be deemed to be so executed.N.I.
14. Any contract or instrument which, if entered into or executed by an individual, would not require to be[F3 executed as a deed] may be entered into or executed on behalf of the[F4 Executive] by any person generally or specially authorised by the[F4 Executive] to act for that purpose, and any document purporting to be such a contract or instrument shall be deemed to be such a contract or instrument until the contrary is proved.N.I.