Colo. Rev. Stat. § 31-23-208
The commission may adopt the plan as a whole by a single resolution or may by successive resolutions adopt successive parts of the plan (said parts corresponding with major geographical sections or divisions of the municipality or with functional subdivisions of the subject matter of the plan) and may adopt any amendment or extension thereof or addition thereto. Before the adoption of the plan or any such part, amendment, extension, or addition, the commission shall hold at least one public hearing thereon, notice of the time and place of which shall be given by one publication in a newspaper of general circulation in the municipality and in the official newspaper of the county affected. The adoption of the plan, any part, amendment, extension, or addition shall be by resolution of the commission carried by the affirmative votes of not less than two-thirds of the entire membership of the commission. The resolution shall refer expressly to the maps and descriptive and other matter intended by the commission to form the whole or part of the plan, and the action taken shall be recorded on the map and plan and descriptive matter by the identifying signature of the chairman or secretary of the commission. An attested copy of the plan or part thereof shall be certified to each governmental body of the territory affected and, after the approval by each body, shall be filed with the county clerk and recorder of each county wherein the territory is located.
C.R.S. § 31-23-208
This section is similar to former § 31-23-108 as it existed prior to 1975.