California Code, Government Code - GOV § 37444

No sale or lease of any property with option to purchase shall be made or entered into pursuant to Section 37442 except when previously authorized by ordinance adopted by a four-fifths vote of all members of the legislative body.  No vote of the electors of the city shall be required to authorize any such sale or lease of property with option to purchase, but any ordinance adopted authorizing such sale or lease shall be subject to referendum in the manner provided by law.