As to any question referred to in § 9-39-30 , fifteen percent of the registered voters residing in a municipality, based upon the total number of registered voters at the last preceding general election, may petition for a special election to determine such question. Source: SL 1955, ch 221 , § 7; SDC Supp 1960, § 45.3907 (2); SL 1987, ch 67 , § 19.