| 1. www.scca.com | Sports Car Club of America |
| 2. www.pca.org | Porsche Club of America |
| 3. www.mcscc.org | Midwestern Council of Sports Car Racing Clubs |
| 4. www.nasaproracing.com | National Auto Sport Association |
| 5. www.hsrrace.com | Historic Sports Car Racing |
| 6. www.britcar.org | British Motor Trade Association |
| 7. www.fot-racing.com | Friends of Triumph |
| 8. www.mgvr.org | MG Vintage Racers |
| 9. www.emraracing.org | EMRA |
| 10. www.av8ss.com | American V8 Supercar Series |
| 11. www.specmiataracing.net | Wheels America |
| 12. www.vararacing.com | Vintage Auto Racing Association |
| 13. www.californiarallyseries.com | California Rally Series |
| 14. www.rimoftheworldrally.com | Western States Rally Championship |
| 15. www.bmwccaclubracing.com | BMW CCA Club Racing |
| 16. www.jcna.com | Jaguar Clubs of North America |
| 17. www.usenduro.com | United States Endurance Racing Association |
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