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Ivalena Vulcheva-Georgieva
„Episkop Konstantin Preslavski” University of Shumen, Faculty of natural sciences, Department “Geography and methodology of teaching geography” Shumen, 9712 Universitetska Str. 115, Bulgaria
Svetla Stankova
„Episkop Konstantin Preslavski” University of Shumen, Faculty of natural sciences, Department “Geography and methodology of teaching geography”Shumen, 9712 Universitetska Str. 115, Bulgaria