Any order or notification published or issued by the Administrator or by the Commissioner of Police or any other police officer under any provision of this Act, and the due publication or issue thereof may be proved by the production of a copy thereof in the Official Gazette, or of a copy thereof signed by the Administrator or Commissioner of Police or other police officer, as the case may be, and by him certified to be a true copy of an original published or issued according to the provisions of this Act applicable thereto.