Slavova-Petkova, Stanislava. “Project ‘Models and Applications of Serious Games in Education of Cultural Heritage and National Identity’”. Digital Presentation and Preservation of Cultural and Scientific Heritage 7 (September 10, 2017): 243–248. Accessed April 20, 2024. https://dipp.math.bas.bg/dipp/article/view/dipp.2017.7.23.