Ohio Rev. Code Ann. § 705.91

All laws pertaining to the initiative and referendum in municipal corporations shall apply to and become a part of each plan of government provided in sections 705.41 to 705.86, inclusive, of the Revised Code. Section 705.92 of the Revised Code shall be submitted, with each such plan, to the electors of the municipal corporation as prescribed in section 705.03 of the Revised Code, and shall go into effect and form a part of any such plan of government only to the extent to which such section has been adopted under section 705.03 of the Revised Code.