70 ILCS 2205/12

All ordinances, orders and resolutions, and the date of publication thereof, may be proven by the certificate of the clerk under the seal of the corporation, and when printed in book or pamphlet form, and purporting to be published by authority of the board of trustees, such book or pamphlet shall be received as evidence of the passage and legal publication thereof, as of the dates mentioned therein, in all courts and places, without further proof.