1. An election to determine the question of incorporation shall be held no later than forty days after the first occurring of either of the following two events: a. The expiration of thirty days from the filing of the original of a decision sustaining the legal sufficiency of the petition and no proceeding having been instituted to review same, or b. The filing of a final order sustaining the petition after such a proceeding to review. c. The procedure for conducting said election shall be pursuant to the election law.