Nielsen, Lars Henrik, Flemming Larsen, and Nils Frandsen. “Upper Triassic-Lower Jurassic Tidal Deposits of the Gassum Formation on Sjælland, Denmark”. Danmarks Geologiske Undersøgelse Serie A 23 (October 16, 1989): 1–30. Accessed May 2, 2024. https://geusjournals.org/index.php/seriea/article/view/7043.