INVOICING INSTRUCTIONS (a) Vendor's invoicing instructions shall be typed upon the face of the formal purchase order. PURCHASE ORDER REVISIONS AND CANCELLATIONS (a) All purchase order revisions shall be written on the Purchase Order Change Form and revisions are to be numbered from the number one consecutively, and reflect the original purchase order number. (1) (2) This revision form shall cover all cancellations and revisions due to price changes, escalator clauses, quantity amounts, typographical errors, etc. The Purchase Change Order shall also indicate reason for the revision and/or cancellation and further reflect monetary increase or decrease as effected by the change. All cancellations initiated at the request of the con- tractor shall be accepted by the vendor in two (2) sign- ed letter copies inscribed, "referenced cancellations are herein acknowledged and accepted at no cost to the buyer." SPECIAL INSPECTION OF MATERIAL (a) Special inspection requirements of material shall be aforestated on the bid quotation request and be further incorpo- rated into the formal purchase order copy. (1) Material inspection shall be accomplished by contractor's engineering personnel as requested by the Procurement Division. (2) Commercial inspection service shall be authorized when- ever necessary as directed by the Procurement Division. PURCHASE ORDER FILING AND DISTRIBUTION (a) Purchase Order File (1) (2) Purchase order numerical file folder shall contain the following data, filed in the following order, top to bottom: bid abstract form, purchase order copy, awardee bid quotation, material receiving reports, other bidders' quotations, other correspondence, telephone memos, telegrams, etc., and material requisition copy. An alphabetic file shall be maintained of purchase orders and be filed by alphabetic reference of the vendor's name. A separate file shall be maintained numerically of purchase order master ditto copies. 13-44