Assenov, Assen, Kiril Vassilev, H. Padeshenko, Boian Koulov, Ekaterina Ivanova, and Bilyana Borisova. “Research of the Biotope Diversity for the Purposes of Economic Valuation of Ecosystem Services in Chepelare Municipality (The Rhodopes Region of Bulgaria)”. European Journal of Sustainable Development 5, no. 4 (October 1, 2016): 409. Accessed December 22, 2024. https://ecsdev.org/ojs/index.php/ejsd/article/view/418.