Section 70 ILCS 15/11 - Purchases and contracts; Promulgation of rules(a) All purchases, contracts or other obligations or expenditures of funds by the Authority must be in accordance with rules and regulations governing the Authority's procurement practice and procedures. The Authority shall promulgate and publish such practices and procedures in sufficient number for distribution to persons interested in bidding on purchases or contracts to be let by the Authority. Such rules and regulations shall be kept on file with the Secretary of the Authority at all times and shall be available for inspection by members of the public at all reasonable times and hours. Such rules and regulations shall be filed and become effective as provided in The Illinois Administrative Procedure Act.
(b) Any contract entered into for purchase or expenditure of funds of the Authority made in violation of this Act, or of any rule or regulation promulgated in pursuance thereof, is void.(c) All sellers to the Authority shall attach to the delivery invoice a statement attesting that the standards set forth in the contracts have been met. The statement must be substantially in the following form: "The Seller, .... hereby certifies that the goods, merchandise and wares shipped in accordance with the attached delivery invoice have met all the required standards set forth in the purchasing contract.
............................ (Seller)"