P. A. Riezebos, M. de Bruin, and R. P. W. Duin. “Ore-Textural and Geochemical Features of Bohnerz and Rasenerz Concretions in Gutland (Luxembourg)”. Netherlands Journal of Geosciences (January 1, 1981): 517-529. Accessed April 3, 2026. https://njgjournal.nl/index.php/njg/article/view/13658.