Iowa Code § 622.96

Proof so made may be perpetuated and preserved for future use by filing the papers above mentioned in the office of the clerk of the district court of the county where the act is done. The original affidavit appended to the notice or paper, if there is one, and, if not, the affidavit by itself is presumptive evidence of the facts stated therein, but does not preclude other modes of proof now held sufficient.