Be it further enacted, That the board shall authorize the issuance of bonds under this Act by a "bond ordinance," subject to the requirements of approval at a special election as provided in this Act or other general law. Such bond ordinance shall contain in substance at least the following provisions:
(a) A statement of the security backing the bonds.
(b) An appropriation of a sum of money for a purpose authorized by this Act or other general law, described in brief and general terms sufficient for reasonable identification, for which the bonds are to be issued.
(c) An authorization for the incurring of indebtedness by the issuance of bonds in a stated amount to finance such an appropriation.
(d) A schedule of the principal maturities and interest payments of the serial bonds, by year.
(e) A schedule of estimated annual payments into the sinking fund, if a sinking fund is required, and the annual amounts of principal and interest, shown separately, to be paid from the fund.
(f) A determination of the period of usefulness of the project, as provided in Section 6.12 of this Act.
(g) A determination of the net debt of the city after issuance of the bonds thereby authorized, and a declaration that the bonds thereby authorized will be within any debt or other limitations of the constitution and laws of this state. [As replaced by Priv. Acts 1963, ch. 74, § 3]