Mo. Rev. Stat. § 492.380

The official character of such officer taking depositions or examinations within any of the United States, or any of the territories of the United States, or in the District of Columbia, authenticated and proved as aforesaid, or by the certificate and seal of the clerk of any court of record within any county of the state or territory, or within the district where such officer resides, and certifying, also, that such officer was an acting judge or associate circuit judge, and duly commissioned as such, at the time when the depositions were taken, shall be a sufficient authentication thereof.