Roszkowska, A., J. Kwolczak, Łukasz Świerszcz, and H. Piecewicz-Szczęsna. “Assessment of Basic Knowledge on Colorectal Cancer and Its Prophylaxis in People Living in Small City and Countryside”. Journal of Education, Health and Sport, vol. 8, no. 9, Sept. 2018, pp. 1028-35, https://apcz.umk.pl/JEHS/article/view/5999.