- American Institute of Certified Public Accountants
- Association of Government Accountants
- Better Business Bureau
- Code of Federal Regulations
- Dun and Bradstreet
- Financial Accounting Standards Board
- Federal Trade Commission
- Fed World
- General Accounting Office
- Government Accounting Standards Board
- Internal Revenue Service
- Library of Congress
- National Association for the Self Employed
- NonProfit Gateway
- Pennsylvania Institute of CPA's
- U.S. Chamber of Commerce
- U.S. Code
- U.S. Department of Commerce
