Thomassen, B, T Tukiainen, and K Secher. “Detailed Investigation of the Niobium-Tantalum Distribution Within the Motzfeldt Centre, South Greenland”. Rapport Grønlands Geologiske Undersøgelse 140 (December 31, 1988): 66–70. Accessed November 27, 2024. https://geusjournals.org/index.php/rapggu/article/view/8038.