Skoczeń, Nikodem, et al. “Analysis of the Impact of Various Social and Demographic Factors on the Incidenceand Level of Severity of Anxiety in a Group of School Students”. Current Problems of Psychiatry, vol. 15, no. 2, Dec. 2014, pp. 78-84, https://czasopisma.umlub.pl/cpp/article/view/2508.