65 ILCS 5/5-1-5
Electors of any city or village specified in Section 5-1-1, equal in number to 1/10 the number of votes cast for all candidates for mayor or president at the last preceding municipal election for such officer, may petition the Chief Judge of the Circuit Court, or any judge of that Circuit designated by the Chief Judge, in which that city or village specified in Section 5-1-1 is located to cause to be submitted to a vote of the electors of that city or village specified in Section 5-1-1 the proposition whether this Article 5 shall be adopted.
Upon submission of such petition the court shall set a date not less than 10 nor more than 30 days thereafter for a hearing on the sufficiency thereof. Notice of the filing of such petition and of such date shall be given in writing to the city or village clerk and to the mayor or village president at least 7 days before the date of such hearing.
If such petition is found sufficient the court shall enter an order to submit that proposition at an election. However, the referendum on the proposition shall not be held on the date of the general primary election for the municipality.
The clerk of the circuit court shall certify the court's order and the proposition for submission.
A proposal to adopt this Article 5 may also be initiated and submitted to the voters in the same manner as is provided in this Section by the adoption of an ordinance by the corporate authorities.
65 ILCS 5/5-1-5