Djekić, T. et al. 2020. LICHENS AS INDICATORS OF AIR QUALITY IN BALNEOLOGICAL CENTER PROLOM BANJA (SOUTHERN SERBIA). Journal of the Geographical Institute “Jovan Cvijić” SASA. 70, 2 (Oct. 2020), 101–113. DOI:https://doi.org/10.2298/IJGI2002101D.