Firlej, Ewelina, Mariola Janiszewska, Mariusz Byzdra, Katarzyna Pawlikowska-Łagód, and Olga Dąbska. 2017. “The Phenomenon of Mobbing in the Opinion of the Professionally Active”. Journal of Education, Health and Sport 7 (7):363-72. https://apcz.umk.pl/JEHS/article/view/4635.