British Harness Racing Club (BHRC)
www.bhrc.org.uk
Irish Harness Racing Association (IHRA)
https://www.irishharnessracing.com
Letrot
https://www.letrot.com
US Trotting Association (USTA)
http://www.ustrotting.com
Standardbred Canada (SC)
https://www.standardbredcanada.ca
European Trotting Union (UET)
https://www.uet-trot.eu
Weatherbys Identification Guide Booklet
colours & marking booklet_10366 (weatherbys.co.uk)
HBLB Code of Practice for Equine Breeding
Code Of Practice : Home (hblb.org.uk)
Wales & Border Harness Racing
www.welsh-trotting.co.uk