If an agency is unable to satisfy requirements for supplies and services from the mandatory sources listed in 8.002 and 8.003, agencies are encouraged to consider satisfying requirements from or through the non-mandatory sources listed in paragraph (a) of this section (not listed in any order of priority) before considering the non-mandatory source listed in paragraph (b) of this section. When satisfying requirements from non-mandatory sources, see 7.105(b) and part 19 regarding consideration of small business, veteran-owned small business, service-disabled veteran-owned small business, HUBZone small business, small disadvantaged business (including 8(a) participants), and women-owned small business concerns.
48 C.F.R. §8.004