E. L. Chistov, E. S. Naboychenko. "REFEREEING IN FUTSAL: WHY ERRORS HAPPEN AND HOW TO PREPARE REFEREES." 5th International Multidisciplinary Scientific Conference on Social Sciences and Arts SGEM 2018 (2018): 705-712. https://doi.org/10.5593/sgemsocial2018/3.5/S13.090