Pay Tax Exemption and Credit Download a PDF certificate or credit letter to share with a supplier before a purchase. Goods Receipt Learn when and how to confirm the delivery of goods and services. Purchase Order Change Shop OnLion Non-converted Orders Decrease/release encumbrance, modify an account assignment, cancel, or change a goods recipient by submitting a Purchase Order Change Form. PSUbuy Directions coming soon. Supplier Process Educate suppliers to update banking information, submit an invoice, select a payment method, or review a payment status. Policy BS13 Payment of Supplier's Invoices Associated with a Purchase Order BS11 Responsibilities after Initiating Purchases From Vendors Outside the University BS12 Payment of Freight and Express Invoices Image