Iowa Code § 558.31
Proof of the due and voluntary execution and delivery of a deed or other instrument may be made before any officer authorized to take acknowledgments, by one competent person other than the vendee or other person to whom the instrument is executed, in the following cases:
[C51, §1220, 1221; R60, §2228; C73, §1959; C97, §2949; C24, 27, 31, 35, 39, §10095; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §558.31]
Referred to in §558.33