The Street Transportation Director shall mail by registered mail to the owner at the address of such owner in the City or elsewhere, if such be known, any notice provided for in this division. In the event that the post office address of the owner is unknown or that the same may not be reached by mail, the Street Transportation Director may publish such notice in the official paper of the City for one publication and such service of such notice shall be complete and shall have the same effect and force as if personally served upon any such owner. (Code 1962, § 35-70; Ord. No. G-3313, § 1)