De Dapper, M., Goossens, R. and Ongena, T. (1989) “The use of SPOT images for the assessment and mapping of geomorphology and land degradation by savanisation in a wet-and-dry tropical forested environment (Lubumbashi, Shaba, Zaire)”, Geografia Fisica e Dinamica Quaternaria, 2, pp. 87–91. Available at: https://www.gfdq.glaciologia.it/index.php/GFDQ/article/view/1140 (Accessed: 2 August 2026).