Thomassen, B. “Evaluation of the Niobium-Tantalum Potential of the Motzfeldt Centre, South Greenland”. Rapport Grønlands Geologiske Undersøgelse 145 (December 31, 1989): 66–73. Accessed July 3, 2024. https://geusjournals.org/index.php/rapggu/article/view/8078.