10 ILCS 5/6-17
Whenever 1,000 of the legal voters in a city of 250,000 population or less where this Article 6 and Articles 14 and 18 of this Act or the Act of which they are a continuation have been adopted shall petition the circuit court in the county in which such city is located to submit to a vote of the electors of such city the proposition as to whether such city and the electors thereof shall reject the Articles, the court shall enter an order of record approving such petition and thereupon the court shall submit such proposition to the legal voters of such city at the next succeeding general, state, county or municipal election to be held in such county in not less than 30 days after the entry of such order. If 1,000 shall exceed one-eighth of the legal voters of any such city then such petition need not be signed or made by more than one-eighth of the legal voters of such city. Notice of election shall be given by the court at least 20 days prior to such election by publication in one or more newspapers of general circulation published within such city.
10 ILCS 5/6-17