TY - CPAPER AU - Hristina Kirova AU - Dimiter Syrakov AU - Maria Prodanova AU - Emilia Georgieva AU - Dimiter Atanassov TI - BACKGROUND CONCENTRATION OF AIR POLLUTANTS FOR SOFIA CITY - ANALYSIS FOR SUMMER AND WINTER MONTHS T2 - SGEM International Multidisciplinary Scientific GeoConference- EXPO Proceedings; 22nd SGEM International Multidisciplinary Scientific GeoConference Proceedings 2022, Energy and Clean Technologies PY - 2022 SP - 279 EP - 286 DO - 10.5593/sgem2022/4.1/s19.36 PB - STEF92 Technology ER -