Mo. Rev. Stat. § 11.060: Official publications — reference to other publications.

If in the compilation of any report or official document, it is necessary to direct the attention of the reader to any matter published in any other official report, or document, of whatsoever office or department, covering any prior period, it shall be done by citing the report, or document, by its proper title and indicating the number of the page at which the matter may be found.