Iowa Code § 446.12
The county treasurer shall obtain a copy of the notice of sale with a certificate of its publication from the printer or publisher, and file it in the office of the treasurer. The certificate shall be substantially in the following form:
I, ................................, publisher (or printer) of the ................................, a newspaper printed and published in the county of ............................ and state of Iowa, certify that the foregoing notice and list were published in that newspaper on the ............ day of ........................, ................, and that copies of each issue of the paper in which the notice and list were published were delivered by carrier or transmitted by mail to each of the subscribers to the paper.
...........................................
Signature of publisher (or printer)
State of Iowa,)
........................ County.) ss.
The above certificate of publication was subscribed and sworn to before me by the above named ................................, who is personally known to me to be the identical person described in the certificate, on the ........................ day of ........................, ................
....................................................
Notary
............................ County, Iowa.
Iowa Code § 446.12
86 Acts, ch 1139, §6; 91 Acts, ch 191, §64