CA Pub Util Code Section 131115

The bonds, or each series thereof, shall be dated and numbered consecutively and shall be signed by the chairperson or vice chairperson of the agency imposing the retail transactions and use tax and the auditor-controller of the agency, and the official seal, if any, of the agency shall be attached. The interest coupons of the bonds shall be signed by the auditor-controller of the agency. All of the signatures and seal may be printed, lithographed, or mechanically reproduced, except that one of the signatures shall be manually affixed. If any officer whose signature appears on the bonds or coupons ceases to be that officer before the delivery of the bonds, the officer’s signature is as effective as if the officer had remained in office.