Popović V, Nikolić M, Katić B. The role of multifunctional agriculture in sustainable tourism development in the area of Stara Planina. EA [Internet]. 2010 Dec. 3 [cited 2024 May 5];57(Spec.num.2):333-42. Available from: https://www.ea.bg.ac.rs/index.php/EA/article/view/953