H. Middelkoop, E. Stouthamer, and W.Z. Hoek. “Geomorphology and Climate – In Honour of Professor Dr Eduard A.Koster”. Netherlands Journal of Geosciences 86 (November 29, 2007): 161 - 164. Accessed March 29, 2026. https://njgjournal.nl/index.php/njg/article/view/11769.