The board of county commissioners may issue bonds of its county for the purpose of building, constructing, repairing or acquiring bridges, and for building and constructing state or county roads and bridges; provided, the issuance of such bonds shall first be approved by not less than three-fifths (3/5) of the qualified voters of the county voting on the question at an election held for such purpose. Such election shall be called and held, and the bonds shall be issued and sold, as in the case of bonds issued for the erection of county hospitals.
Okla. Stat. tit. 69, § 604