Pub. Util. Code, § 29170

Bonds may be issued in form payable to bearer, with coupons attached for payment of interest and, if so issued, may be made subject to registration. Bonds issued in bearer form shall constitute negotiable instruments for all purposes under the laws of the State of California. The district may appoint a registration agent which may be a bank or trust company and authorize such registration agent to maintain books of registry and to register, authenticate and exchange bonds on such terms and conditions and pursuant to such rules and regulations as the district may provide. The district may provide for the interchange of coupon bonds for registered bonds and registered bonds for coupon bonds, and may provide that the bonds shall be registered as to principal only, or as to both principal and interest, or otherwise, as the district may determine.