1.11.020

When the summons and complaint cannot by reasonable diligence be personally served on the defendant in the manner specified in Article XI, Section 1, service may be made either by mail or publication. In the case of service by mail, true copies of the summons and complaint shall be sent by registered or certified mail to the defendant's last known address. A return receipt for mail delivery signed by the defendant shall be returned to the Clerk and filed in the docket and shall constitute proof of service by mail.