A. Korcz, M. Bronikowska, I. Laudanska-Krzeminska, J. Borowiec, M. Ludwiczak, and M. Bronikowski, “Is social support during physical education lessons associated with body mass index status, gender and age?”, SA J. Res. Sp., vol. 40, no. 2, pp. 53–68, Aug. 2018.