Sadowski, Ryszard F. “The Concept of Nobilis Barbarus in the Light of Contemporary Ecological Challenges”. Problemy Ekorozwoju / Problems of Sustainable Development 11, no. 1 (January 4, 2016): 23–30. Accessed January 10, 2026. https://ph.pollub.pl/index.php/preko/article/view/4956.