J. . Payne, N. . Routledge, S. . Charlton, and A. . Hunnisett, “Effects of Rider Weight and Pony Age on Epaxial Muscle Pain Sensitivity and Heart Rate Variability in Exmoor Ponies: A Preliminary Study”, Int J Equine Sci, vol. 5, no. 2, pp. 138–144, Aug. 2026, doi: 10.64292/ijes.229.