50 ILCS 220/5

Any amendment which may be made to any code or public record incorporated by reference by a municipality hereunder, may be likewise adopted by reference provided that the required number of amended or corrected copies are filed with the clerk of such municipality for inspection, use, and examination by the public. Ordinances adopting amendments by reference shall be required to be published as any other ordinances of the municipality and the requirement as to prior filing before passage shall apply likewise to amendments.