Iowa Code § 661.6
If such duty, the performance of which is sought to be compelled, is not one resulting from an office, trust, or station, it must be one for the breach of which a legal right to damages is already complete at the commencement of the action, and must also be a duty of which a court of equity would enforce the performance.
[R60, §3767; C73, §3375; C97, §4343; C24, 27, 31, 35, 39, §12445; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §661.6]