Ommeren, H.R. van. “C.A.A. Linssen, Historische Opstellen over Lotharingen En Maastricht in De Middeleeuwen”. BMGN - Low Countries Historical Review 102, no. 2 (January 1, 1987): 282–284. Accessed March 29, 2024. https://bmgn-lchr.nl/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-103171.