The provisions of this part shall apply to any municipality having a police department under the management of a commissioner, superintendent, board of police commissioners or police committee, which accepts the provisions of this part by an affirmative vote of the electors of such municipality at a referendum warned and held for the purpose of accepting the same in the manner prescribed in section 9-369. In any such referendum election, the designation of the question on the voting tabulator ballot shall be “Shall a Police Reserve Fund be established?”. The provisions hereof shall not apply to cities authorized by special charter to establish a police benefit or reserve fund.