Sections 3A-13 through 3A-23 apply to any district, regardless of the population of the district and of the law under which it is organized and operating, and constitute complete authority for issuing refunding bonds as therein provided without reference to other laws. Those Sections shall be construed as conferring powers in addition to, but not as limiting powers granted under, other laws or other provisions of this Act.
110 ILCS 805/3A-23