Section 651. Petition

Upon  the  filing  with  the clerk of the board of
  supervisors of a petition signed by electors  of  the  county  equal  in
  number  to  at least ten per centum of the whole number of votes cast in
  the county for governor at the last gubernatorial election asking that a
  referendum be held on the question of adopting one  of  the  alternative
  forms  of  county government authorized by this chapter, with or without
  variations, the board of supervisors shall  cause  the  question  to  be
  submitted  to  the  electors  of  the  county  in the manner hereinafter
  provided. Proceedings may be instituted and maintained  to  contest  the
  sufficiency  and  validity of any petition in the manner provided in the
  election law, as though such petition were a  designating  petition.  If
  the  petition be sufficient and valid, the board of supervisors shall by
  resolution cause the question to be submitted to  the  electors  of  the
  county  for  approval  or  disapproval  at  the  next  general  election
  occurring in an odd-numbered year and not less than sixty days after the
  date on which the petition is filed.