39 C.F.R. § 601.100 Purchasing policy.
Title 39 - Postal Service
It is the policy of the Postal Service to acquire property and services in accordance with 39 U.S.C. 410 and all other applicable public laws enacted by Congress.
Title 39: Postal Service
PART 601—PURCHASING OF PROPERTY AND SERVICES
§ 601.100 Purchasing policy.

