A. If within thirty days following the adoption of an ordinance, a petition signed by registered voters in a number more than twenty percent of the number of voters who voted at the previous regular municipal election is presented to the Commission, asking that the ordinance in question be submitted to a special election for its adoption or rejection, the ordinance shall become ineffective and the Commission shall provide for an election on the measure within sixty days of the filing of the petition.

B. The ballot shall contain the text of the ordinance in question. Below the text shall be phrases:

“For the above measure,”

and

“Against the above measure,”

followed by spaces for marking with a cross the phrase desired. If a majority of the votes cast favor the measure, it shall take effect immediately. If a majority of the votes cast are against the measure, it shall not take effect.

C. If an ordinance is an emergency measure, it shall go into effect immediately, but it may be repealed by an adverse majority at a referendum election.