Authors
Svetla Stankova
Konstantin Preslavski University of Shumen, Faculty of Natural Sciences, Department of Geography, Regional Development and Tourism, Shumen, Bulgaria
Petya Guteva
Konstantin Preslavski University of Shumen, Faculty of Natural Sciences, Department of Geography, Regional Development and Tourism, Shumen, Bulgaria
Tzanko Tzankov
South-West University Neofit Rilski, Faculty of Mathematics and Natural Sciences, Department of Geography, Ecology and Environment Protection, Blagoevgrad, Bulgaria