that the other party hereto shall bring all of their portion of such fence to such tight fence condition within ninety days. Under the doctrine of incorporation, an extrinsic document becomes part of the contract by reference to that document in the contract. Hofmeyer v. Iowa Dist. Ct., 640 N.W.2d 225, 228 (Iowa 2001). The doctrine of incorporation requires the contract to make a clear and specific reference to an extrinsic document to incorporate the document into the contract. In re Estate of Kokjohn (Kokjohn v. Harrington), 531 N.W.2d 99, 100-01 (Iowa 1995). Whether a contract incorporates extrinsic material presents a question of law. Hofmeyer, 640 N.W.2d at 228. Statutes and administrative rules can become part of a contract under the doctrine of incorporation. See id. at 229 (<HOLDING>); 11 Richard A. Lord, Williston on Contracts §
holding that the plaintiffs claims arose from a certain contract because the subject matter of the plaintiffs suit was intertwined with requirements referred to in the contract holding that nonsignatories to a contract have no rights under the contract and thus no standing to assert claims under the contract holding an administrative rule referred to in the contract became part of the contract under the doctrine of incorporation holding that the law of the state of incorporation applies holding that an attorney approval clause in a contract for the sale of real estate was a part of that contract and would have to be satisfied for the underlying contract to be enforceable