Mo. Rev. Stat. § 72.060
Any city, town or village within this state, now incorporated under the provisions of this chapter, or under any special or local law, as a village, town or city, either of the second, third or fourth classes, as classified in said chapter, and in which the citizens thereof desire incorporation as a village, town or city of a higher class, and believe that since the taking of the last census, state or national, there has been sufficient increase in population to entitle it to such desired incorporation, may, by authority of an ordinance, and at the expense of such village, town or city, cause to be taken a census of its population, and should such census, when so taken, show that the village, town or city taking the same, has the requisite population to entitle it to the right to become incorporated as a village, town or city of the higher class, then such village, town or city may proceed to secure such incorporation as its population may then entitle it to, under and by authority of the provisions of this chapter; provided, that cities or towns that have permitted their organization to become dormant or ineffective, through a failure to elect corporate officers or levy a corporate tax for the two years immediately preceding, may, by a petition of the majority of the taxpayers of such city or town to the county commission, have an enumeration taken and be assigned to its proper class; and thereupon the county commission shall appoint the proper officers for such city or town, who shall hold their office until the next municipal election thereafter and until their successors are elected and qualified.
§ 72.060, RSMo