Mo. Rev. Stat. § 136.120

The director of revenue shall have the power to prescribe such rules and regulations, not inconsistent with other provisions of law, as may be necessary to the efficient conduct of the division of taxation and collection. The director of revenue shall have the power to publish from time to time in pamphlet or booklet form said rules and regulations and the tax, licensing and fee laws of the state of Missouri. He shall distribute copies thereof for use of the public, but in his discretion may require payment of a reasonable charge therefor.