THE IMPACT OF COVID-19 ON URBAN TOURISM IN BULGARIA: ECONOMIC, SOCIAL AND ENVIRONMENTAL PERSPECTIVES. TRAKIA JOURNAL OF SCIENCES, [S. l.], v. 23, n. Supplement 2, p. 8, 2025. DOI: 10.15547/tjs.2025.s.02.066. Disponível em: https://tjs.trakia-uni.bg/index.php/tjs/article/view/230.. Acesso em: 22 oct. 2025.