Cal. Pub. Res. Code § 13115

The bonds shall be signed by the chair of the board and countersigned by the clerk of the board or the clerk’s deputy and the coupons shall be signed by the clerk of the board or the clerk’s deputy. All signatures, except that of the clerk, on the bonds may be printed, lithographed, or engraved. If an officer whose signature appears on the bonds or coupons ceases to be an officer before the delivery of the bonds, the signature is as effective as if the officer had remained in office. All bonds shall be payable at the office of the county treasurer, who is the depositary of the district.