Chudzik, R., and P. Rybojad. “The Number of Passively Smoked Cigarettes and the Risk of Lung Cancer Among the Inhabitants of the Świętokrzyskie Region (2010-2018)”. Journal of Education, Health and Sport, vol. 11, no. 9, Sept. 2021, pp. 344-50, doi:10.12775/JEHS.2021.11.09.043.