20.—(1) The application of the seal of the Commissioners must be authenticated by the signature of the chair of the Commissioners or some other Commissioner authorised by the Commissioners to authenticate the application of the seal, and of any officer of the Commissioners authorised by the Commissioners to act in that behalf.
(2) Any notice, licence or other document given or issued by the Commissioners must, unless the contrary intention is expressed, be sufficiently authorised if signed by a duly authorised officer of the Commissioners.