CA Pub Util Code Section 180257

The bonds, or each series thereof, shall be dated and numbered consecutively and shall be signed by the chairperson or vice chairperson of the authority and the auditor-controller of the authority, and the official seal, if any, of the authority shall be attached. The interest coupons of the bonds shall be signed by the auditor-controller of the authority. All of the signatures and seal may be printed, lithographed, or mechanically reproduced. 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.