At any time after the establishment of a district library, any county, municipality, or township having its own public tax supported library and contiguous to the district may become a part of the district if the proposition is submitted to the voters of both the district and of the county, municipality, or township at an election in accordance with the Election Code and the proposition is approved by a majority of the voters of the district and of the county, municipality, or township voting upon the proposition. The annexation procedures in this Act shall govern the election for inclusion within an existing district.
75 ILCS 16/15-95