ANGELOVA, D. Karst Types in Bulgaria. Acta Carsologica, Ljubljana, Slovenija, v. 32, n. 1, 2016. DOI: 10.3986/ac.v32i1.360. Disponível em: https://ojs.zrc-sazu.si/carsologica/article/view/360. Acesso em: 4 may. 2024.