1. WHO. European health for all database (HFA-DB), World Health Organization Regional Office for Europe Updated: January 2013; 2013. (available at: https:// gateway.euro.who.int/en/datasets/european- health-for-all-database/).;
2. Institut za javno zdravlje Srbije "Dr Milan Jovanović Batut". Rezultati istraživanja zdravlja stanovništva Srbije, 2013. godina, Beograd 2014 (available at:http://www. batut.org.rs/download/publikacije/ IstrazivanjeZdravljaStanovnistvaRS2013. pdf);
3. Institut za javno zdravlje Srbije "Dr Milan Jovanović Batut". Zdravstveno- statistički godišnjak Republike Srbije 2015; Beograd, 2016 (available at: http:// www.batut.org.rs/download/publikacije/ pub2015.pdf);
4. Weiss G, Steinacher I, Lamprecht B, Schirnhofer L, Kaiser B, Sönnichsen A, Studnicka M. Detection of Chronic Obstructive Pulmonary Disease in Primary Care in Salzburg, Austria: Findings from the Real World. Respiration 2014;87:136-143, https://doi.org/10.1159/000354796.;
5. Walters JAE, Crockett AJ, McDonald VM. COPD -practical aspect of case finding, diagnosing and monitoring. MedicineToday 2013; 14(2): 32-40.;