Ravikumar, Velusamy, and S. Chandrakumarmangalam. “Impoverishment – The Threat for Sustainable Developments in Developing Countries”. Problemy Ekorozwoju 11, no. 2 (July 1, 2016): 105–111. Accessed July 22, 2024. https://ph.pollub.pl/index.php/preko/article/view/4949.