50 ILCS 420/4
In order to authorize and issue the Notes the Governing Body shall adopt an ordinance (or resolution where appropriate) fixing the amount of Notes, the date thereof, the maturity thereof, rate of interest thereof unless the Notes are to be sold by public bid, place of payment and denomination, which shall be in equal multiples of $1,000, and provide for the levy and collection of a direct annual tax upon all the taxable property in the Unit of Government sufficient to pay the principal of and interest on the Notes to maturity. Upon the filing in the office of the county clerk in each county in which the Unit of Government is located of a certified copy of such an ordinance (or resolution where appropriate), adopted by the Governing Body it shall be the duty annually of the county clerk to extend the tax therefor in addition to and in excess of all other taxes heretofore or hereafter authorized to be levied by such Unit of Government or on behalf of such Unit of Government.
50 ILCS 420/4