Chapter 9 - Required Sources of Supplies and Services 9-1. Required Sources9-2. AbilityOne9-3. UNICOR/Federal Prison Industries9-4. Computer Hardware, Enterprise Software and Solutions (CHESS)9-5. U.S. Navy’s Spiral 3 Contracts9-6. DLA Document Services9-7. Supplemental Procurement Guidance9-8. E-Commerce PlatformsParent topic: APPENDIX - EE DEPARTMENT OF THE ARMY GOVERNMENT PURCHASE CARD OPERATING PROCEDURES