70 ILCS 1505/8

All ordinances, orders, and resolutions of the Chicago Park District may be proved by the certificate of its secretary under the seal of the district and when printed in book or pamphlet form and purporting to be published by the commissioners, such book or pamphlet shall be received as evidence of the passage of such ordinances, orders, and resolutions as of the dates mentioned in such publications, in all courts or places without further proof.