Ed. Code, § 19180

The board of supervisors of any county in which there has been established a county free library which does not serve the entire county may, on behalf of the county free library, construct, build, repair or refurnish buildings to be used for county free library purposes, payment for which may be made from the general fund of the county. If payment is made from the county’s general fund, the county auditor shall each fiscal year thereafter transfer from the county free library fund to the county’s general fund as a prior claim against the county free library fund for as many years as are determined by the board of supervisors but not to exceed 20, an equal annual installment in such amount that over the designated period of years the entire payment from the county’s general fund will be completely repaid. Payment of the costs of the construction of a county free library building may also be made from the employees retirement fund of a retirement system established under the authority of the County Employees Retirement Law of 1937 as an investment of that fund and under the conditions specified in that law.