In Wadsworth v. Moe, 53 Wis. 2d 620, 624-25, 193 N.W.2d 645 (1972), the supreme court summarized the principles relevant to whether the statute of frauds may be met by the use of extrinsic evidence: To consider extrinsic evidence not found on the face of the contract there must be something in the document that furnishes some foundation, link, or key to the oral or extrinsic testimony which identifies the property. ... The function of the extrinsic evidence must be limited to the identification of the real estate. That evidence cannot be used to supply a portion of the description or to establish the intent of the parties."