Igoe BA, Browne D. Maximum ball in play demands for sub-elite Rugby Union referees in domestic club rugby. J. Hum. Sport Exerc. [Internet]. 2020 Sep. 1 [cited 2024 May 3];15(3):478-8. Available from: https://www.jhse.ua.es/article/view/2020-v15-n3-maximum-ball-play-demands-sub-elite-rugby-union-refe