Comparative analysis of health problems in students from elementary school and middle school in Lublin, 2010–2015 - Kocka, Katarzyna; Ślusarska, Barbara; Bartoszek, Agnieszka; Rząca, Marcin; Zdybel-Fałdyga, Urszula; Nowicki, Grzegorz; Naylor, Katarzyna (Family Medicine & Primary Care Review, 2018)