Upon the written application of 10 percent of the registered voters in a town, presented to the selectmen or one of them at least 15 days before the day prescribed for an annual town meeting, the selectmen shall insert in their warrant for such meeting an article relative to the use of fluoride in the public water system for said town. If the town has an official ballot, the town clerk shall insert on such ballot the following question: “Shall fluoride be used in the public water system?” Beside this question shall be printed the word “yes” and the word “no” with the proper boxes for the voter to indicate his or her choice. If a majority of those voting in a water system that serves one municipality does not approve the use of fluoride in the public water system, no fluoride shall be introduced into the public water system for said town; or if fluoride has prior to said vote, been introduced, such use shall be discontinued until such time as the majority of those voting in the town approve the use of fluoride. After such popular referendum, the selectmen shall not insert an article relative to the use of fluoride in the public water system in the warrant nor shall such question be inserted on the official ballot for a minimum period of 3 years from the date of the last popular referendum and only upon written application at that time of not less than 10 percent of the registered voters of said town. The procedure for a referendum on the use of fluoride in a town that is part of public water system serving more than one municipality shall be the procedure in N.H. Rev. Stat. § 485:14-a.