Cal. Ed. Code § 89601
In order to encourage qualified teachers to enter and remain in service with the California State University, an optional retirement program is authorized by this chapter. The optional retirement program may be established on or after July 1, 1991, by a provision adopting this chapter in a memorandum of understanding which is entered into by the trustees pursuant to Chapter 12 (commencing with Section 3560) of Division 4 of Title 1 of the Government Code. However, no other provision of this chapter is subject to the control of any memorandum of understanding. The optional retirement program shall become operative on the July 1 which immediately follows the receipt by the Public Employees' Retirement System of a notice of the adoption of this chapter and a copy of the memorandum of understanding.
Ca. Educ. Code § 89601