Colo. Rev. Stat. § 31-12-307
All ballots or voting machine tabs prepared for use pursuant to this part 3 shall contain the propositions For Annexation and Against Annexation. If the question is submitted on paper ballots, such ballots shall be deposited in a separate ballot box used for that purpose only.
Source: L. 75: Entire title R&RE, p. 1095, § 1, effective July 1.
Editor's note: This section is similar to former § 31-8-205 as it existed prior to 1975.