6939.7. The bonds of any issue may be issued in one or more series. The bonds of such series shall be payable within 30 years from their date and shall mature serially at such times as may be fixed by the board, but the earliest maturityof the principal of the bonds of any series shall be fixed at a date not more than 10 years from the date of issue of such series.
(Added by Stats. 1961, Ch. 1457.)