A broker's right to commissions for procuring the execution of a contract for an exchange of property being absolute, when the written contract of exchange was entered into, was not affected by the non-completion of the contract caused by the inability or unwillingness of one of the parties to perform. Tieck v. Mc-Kenno, 101 N. Y. S. 317, 115 App. Div. 701; Goodrich v. Tur-ney, 186 P. 806, - Cal. App. - . See also Secs. 458, 460, 464.