Sec. 20-12   Referendum; submission by council; time, restriction
   The council by resolution may submit to a referendum for adoption or rejection at any general, primary, or special election held in the City, any proposed ordinance or measure or a proposal for the repeal or the amendment of any ordinance in the same manner and with the same force and effect as provided in this chapter for submission on petition. No such ordinance or amendment shall be submitted, however, at any election to be held in less than thirty (30) days from the date of the meeting of the council when such ordinance or amendment is ordered submitted.