1. Bangsbo, J, Norregaard, L, and Thorsoe, F. Activity profile of competition soccer.;Can J Sport Sci,1991
2. Castagna, C and Abt, G. Intermatch variation of match activity in elite Italian soccer referees.;J Strength Cond Res,2003
3. Castagna, C, Abt, G, and DOttavio, S. Relation between fitness tests and match performance in elite Italian soccer referees.;J Strength Cond Res,2002
4. Castagna, C and DOttavio, S. Effect of maximal aerobic power on match performance in elite soccer referees.;J Strength Cond Res,2001
5. Catteral, C, Reilly, T, Atkinson, G, and Coldwells, A. Analysis of work rate and heart rates of association football referees.;Br J Sports Med,1993