Musa Ahmed, Shamseddin, and Lars Ribbe. “Analysis of Water Footprints of Rainfed and Irrigated Crops in Sudan”. JNRD - Journal of Natural Resources and Development 1 (December 6, 2011): 20–28. Accessed December 8, 2024. https://journals.ub.uni-koeln.de/index.php/JNRD/article/view/658.