Cal. Gov. Code § 22308

This article does not apply to a retirement system composed of the positions of members of a divided system who desire coverage under the federal system as defined in subdivision (m) of Section 22009.1 and wherever in this part the conduct of a referendum is made a condition, the condition shall be fully satisfied by compliance with Article 2.5 (commencing with Section 22150) of Chapter 1 as to that retirement system.