Mo. Rev. Stat. § 486.340
3. The affidavit of executing witness for acknowledgment by an individual who does not appear before a notary shall be in type not smaller than eight-point and in substantially the following form:
I, ______ (name of executing witness), do solemnly affirm under the penalty of perjury, that ______ (name of person who does not appear before a notary), personally known to me, has executed the within ______ (type of document) in my presence, and has acknowledged to me that ______ (he/she) executed the same for the purposes therein stated and requested that I sign my name on the within document as an executing witness.______ (signature of executing witness)
Subscribed and affirmed before me this ______ day of ______, 20____________ (official signature and official seal of notary)
(L. 1977 H.B. 513 § 30, A.L. 2004 H.B. 1193)