472.110. Proof of service in all cases requiring noticewhether by publication, mailing or otherwise, shall be filedbefore the hearing. Service made by a private person shall beproved by the affidavit of the person or by acknowledgment ofservice; service made by the clerk, sheriff or other officialshall be proved by certificate or return of service. Proof ofservice by publication shall be made in the form of the affidavitprescribed by section 493.060, RSMo. In the case of service byregistered or certified mail, where the court requires a returnreceipt, the return receipt shall be attached to the proof ofservice if a receipt has been received; if no receipt has beenreceived, or in case a notice served by ordinary mail is returnedto the sender, the court may, in its discretion, order furtherservice on the party.
(L. 1955 p. 385 ยง 12, A.L. 1957 p. 829, A.L. 1980 S.B. 637)Effective 1-1-81