TY - CPAPER AU - Kliment Naydenov TI - BULGARIAN CASE STUDIES IN IMPROVING URBAN AIR QUALITY T2 - SGEM International Multidisciplinary Scientific GeoConference- EXPO Proceedings; 22nd SGEM International Multidisciplinary Scientific GeoConference Proceedings 2022, Energy and Clean Technologies PY - 2022 SP - 287 EP - 294 DO - 10.5593/sgem2022/4.1/s19.37 PB - STEF92 Technology ER -