delivered the opinion of the court.
Plaintiff filed a complaint alleging that defendant owed him $3,881.99 for two Zeon signs. Defendant denied generally and asserted that the complaint failed to state a claim upon which relief could be granted. The case was heard without a jury, and the court decreed that the plaintiff have and recover the $3,881.99, finding inter alia that the parties entered into a verbal agreement whereby the defendant was to assume the liability and obligation of the plaintiff for the signs.
Prior to September 24, 1962, the parties had negotiated for the sale of plaintiff’s business, and a written agreement was entered into on September 24, providing for *626 the sale of “all General Motors Corporation, Buick-Pontiac automobile and G.M.C. truck parts; and all shop equipment, office equipment, and parts bins,” and indicating that plaintiff would comply with the Bulk Sales Law or furnish defendant with an affidavit to the effect that there were no unpaid creditors. 1 Defendant was to be at a new location and plaintiff testified that at the time the written agreement was being prepared he indicated he wished that agreement to encompass arrangements concerning five signs which he had leased. Three of these were billboards signs, which defendant later used after making necessary arrangements with the lessor, and two were the Zeon signs, over which the present controversy arose, one of which was located on plaintiff’s building and the other at his used car lot. The attorney who drew the written agreement first testified that defendant had said he would hold plaintiff harmless as far as any other payments on the sign, but on cross-examination said probably the word “harmless” was not used but that defendant had said he was “holding” so that plaintiff would not be responsible for the indebtedness. .According to plaintiff:
“ * * * everything went into the agreement with the exception of the signs and when we came to the signs, Mr. Lefforge stated that he would rather leave the signs out of the buy and sell agreement, and I said, well, after all, I don’t want to be stuck with the signs because after all if I go out of business I have no further use for the signs, and at this point Mr. Lefforge stated that he would like to have the opportunity to deal with the sign companies himself. He made the statement that I was probably paying too much money for the rental of the signs and that he would rather deal directly with them * * * [and] that spending this kind of money * * * [his] word ought to be good for some signs. * ■ * * he said, T will deal direct with the sign people myself. I will make my own deal with them.’ And I said, ‘Well, what about me ?’ And he said, ‘You have no more worries. I will get them off of your back and I will deal with the sign people direct.’ * * * ‘You are not going to be stuck for these signs * ⅜ ⅝ ⅝ **
Following the date of the sale of the agency, defendant had certain negotiations with the lessor of the two Zeon signs but finally wrote the company a letter saying there 'was no use of contacting him further until there was a better price. Thereafter, the sign company sued plaintiff and secured judgment for the amount claimed in this litigation.
Appeal has been taken from the court’s judgment decreeing that plaintiff have and recover the $3,881.99, defendant urging that the court erred in four different respects. It is first contended that the written agreement between the parties is controlling so that the plaintiff could not show by parol testimony that the parties had an oral, collateral agreement regarding the signs, and secondly, that the essential elements of a binding collateral contract, including mutual assent and consideration, are not shown by the evidence. Finally, it is argued that any alleged oral contract is unenforceable because of the violation of the statute of frauds and that the amount of the judgment awarded by the trial court is excessive because plaintiff failed to mitigate the damages as required by law.
As to defendant’s first and second charges of error, he cites 32A C.J.S. Evidence § 901 for the statement:
“ * * * it is established that, with certain exceptions * * * such as fraud, *627 accident, mistake, or ambiguity, parol or extrinsic evidence is not admissible to vary, add to, modify, or contradict the terms or provisions of the written instrument * * *.
“Where the parties have deliberately put their engagements into writing in such terms as import a legal obligation, without any uncertainty as to the object or extent of their engagement, all previous or contemporaneous negotiations and agreements with reference to the subject matter are, or are presumed or considered to have been, merged in, or superseded by, the written contract, and the whole engagement of the parties and the extent of their undertaking is conclusively presumed, or at least they are prima facie presumed, to have been reduced to writing. In such cases, the writing is regarded as the only evidence of the agreement * * *»
Defendant bolsters the mentioned rule with numerous cases, including that of Demple v. Carroll,
In the instant case, there was no proof that the execution of the written contract was consideration for the alleged oral agreement or that there existed any other consideration for it. Furthermore, this court is unwilling to say that under the circumstances here present Langenback v. Mays, supra, dealing with a particular type of situation, is authority for plaintiff’s position that one contract may be the consideration of another. Accordingly, the judgment must be reversed. It, therefore, becomes unnecessary to enter into a discussion of defendant’s allegations of error that any alleged oral contract is unenforceable because of the violation of the statute of frauds and that the amount of the judgment awarded by the trial court is excessive because plaintiff failed to mitigate the damages as required by law.
Reversed.
Notes
. The affidavit was subsequently provided and stated that “the affiant has no unpaid bills or accounts due and owing by him to anyone in connection with the automobile and truck business carried on by him during the time he has been in Rawlins. ⅜ ⅜ ⅜ the only bills duo and owing by the affiant would be those bills contracted each month in connection with wages, rent and current operating expenses paid on a monthly basis.”
