BULLA, Miklós; GUZLI, Piroska. Indicators of sustainability. TÁJÖKOLÓGIAI LAPOK, [S. l.], v. 6, n. 1-2, p. 1–15, 2008. DOI: 10.56617/tl.4145. Disponível em: https://journal.uni-mate.hu/index.php/tl/article/view/4145. Acesso em: 10 apr. 2025.