Depositions or examinations taken by any person or judicial officer without the United States, by virtue of any commission issued in pursuance of sections 492.080 to 492.400 shall be, except as herein otherwise provided, accompanied by a certificate of the official character of said officer, attested by the seal of state, or of a court of the government in which the depositions or examinations were taken.
§ 492.390, RSMo