35 ILCS 143/10-40: Invoices.

Every distributor or other person who purchases tobacco products for resale for shipment into Illinois from a point outside Illinois shall procure invoices in duplicate covering each shipment and shall make the invoices available for inspection upon demand by a duly authorized employee of the Department, and shall, if the Department so requires, furnish one copy of each invoice to the Department at the time of filing the return required by this Act.