Ivanova E, Koulov B, Borisova B, Assenov A, Vassilev K. GIS-based Valuation of Ecosystem Services in Mountain Regions: A Case Study of the Chepelare Municipality in Bulgaria. EJSD [Internet]. 2016Oct.1 [cited 2024Apr.24];5(4):335. Available from: https://www.ecsdev.org/ojs/index.php/ejsd/article/view/409