Trikalis Χρήστος, Papanikolaou Ζήσης, Soulas Δημήτριος, and Gerodimos Βασίλειος. 2007. “Evaluation of the Speed and Aerobic Capacity of Elite Greek Soccer Referees in A΄ and B΄ National Division”. Inquiries in Physical Education and Sport 5 (3):445-50. https://journals.lib.uth.gr/index.php/inquiries/article/view/1224.