Colo. Rev. Stat. § 31-21-302
The issuance of any bonds in accordance with this part 3 shall be authorized by an ordinance, subject to and otherwise in accordance with the provisions of section 31-15-302(1)(d). Such bonds shall bear interest at a rate and shall be exchanged or sold at a price such that the net effective interest rate of the issue of bonds does not exceed the maximum net effective interest rate authorized. Interest shall be paid semiannually at such place, in such denominations, and by such officers as may be prescribed in such ordinance. Such bonds may be exchanged for outstanding matured and overdue special assessment bonds or obligations and interest thereon, or they may be sold and the proceeds thereof used for the purpose specified in this part 3.
C.R.S. § 31-21-302
This section is similar to former § 31-21-303 as it existed prior to 1975.