32-2-262. Consent of agent. The written consent of the person so designated to act as agent shall also be filed in like manner, and such designation shall remain in force until the filing in the same offices of a written revocation thereof or of a consent executed in like manner. A certified copy of a designation so filed, accompanied with a certificate that it has not been revoked, is presumptive evidence of the execution thereof and conclusive evidence of the authority of the officer executing it.