https://www.gao.gov/products/403470

A-49009,A-51607: May 01, 1950

THE FOLLOWING CERTIFICATE ON SUCH DOCUMENTS WILL BE SUFFICIENT AND IS HEREBY APPROVED: "I CERTIFY THAT THE ABOVE BILL IS CORRECT AND JUST AND THAT PAYMENT THEREFOR HAS NOT BEEN RECEIVED." 2. WHERE PURCHASES ARE MADE UNDER CONTRACTS WHICH PROVIDE THAT UNIT PRICES OF GASOLINE OR OTHER PETROLEUM PRODUCTS SHALL BE BASED ON POSTED TANK WAGON. WHERE PURCHASES ARE MADE UNDER CONTRACTS CONTAINING AN ARTIC...

https://www.gao.gov/products/474673

A-49009,A-51607: Jun 03, 1942

Prescribed that the following certificate be used in lieu of all others by vendors and contractors in support of invoices or public vouchers covering purchases and services other than personal: "I certify that the above bill is correct and just. All conditions of purchase applicable to the transactions have been complied with. That State or local sales taxes are not included in the amounts billed...