(75 ILCS 16/15-15)
    Sec. 15-15. Territory included within municipality or school district.
    (a) A district may, by ordinance and referendum, annex territory if that territory is:
        (1) located within the boundaries of a municipality
    
or school district that is included, entirely or partially, within the district;
        (2) contiguous to the district; and
        (3) without local, tax-supported public library
    
service.
An ordinance under this subsection must describe the territory to be annexed. Prior to adopting the ordinance, the board of trustees of the library district shall send notice of the proposed ordinance to the president of the board of trustees of each public library located within one mile of the territory to be annexed. The library district may, in addition, provide notice of a proposed annexation ordinance on a website maintained by the library district. At any meeting of the board of trustees in which an annexation ordinance under this Section is considered, the board shall provide a reasonable opportunity for any interested person to make public comments on the proposed annexation ordinance.
    (b) Within 15 days of the passage of the annexation ordinance, the library district shall send notice of the adoption of the ordinance, a copy of the map showing the boundaries of the territory to be annexed, and a copy of the text of the publication notice required in this Section to the president of the board of trustees of each public library with territory within one mile of the territory to be annexed. Within 15 days after the adoption of the ordinance it shall be published as provided in Section 1-30. The board may vacate an annexation ordinance before its publication.
    (c) The publication or posting of the ordinance shall include a notice of the question of the adoption of the ordinance to be submitted to the voters of the district or the territory to be annexed and the date of the prospective referendum.
    (d) Upon the passage of the annexation ordinance under this Section, the board of trustees shall certify the question to the proper election authority, who shall submit the question at the next regular election. Notice of this election shall be given and the election shall be conducted in accordance with the Election Code. The proposition shall be submitted to the voters in substantially the following form:
        Shall (description of territory) be annexed to (name
    
of public library district), (location), Illinois?
    (e) If a majority of votes cast upon the proposition in the district, and also a majority of votes cast upon the proposition in the territory to be annexed, are in favor of the proposition, the Board of Trustees of the library district may conclude the annexation of the territory.
    (f) If, before the effective date of this amendatory Act of the 101st General Assembly, a district has annexed territory under this Section, that annexation is hereby validated, ratified, and declared to be in full force and effect.
(Source: P.A. 101-99, eff. 7-19-19.)