Cal. Gov. Code § 38502

If the land comprising all or any part of such park has been purchased from funds realized from the sale of bonds of a bond issue authorized for the purpose of acquiring the land for park purposes, the question of abandonment of all or a part of the park and the sale or conveyance of the land shall first be submitted to, and approved by, the voters of the city at the next municipal election or at a special election called for that purpose.