Mo. Rev. Stat. § 493.027

In any first classification county, or in any city not within a county, a board consisting of the judges of the circuit court of such county, or a majority of them, if they deem it in the public interest, may qualify any newspaper of general circulation, and as further qualified in section 493.050, for the publication of public notices and advertisements, and may review and approve rates which may be charged for public notices and advertisements.