Kalsbeek, F, and H.F Jepsen. 1980. “Preliminary Rb-Sr Isotope Evidence on the Age and Metamorphic History of the North Greenland Crystalline Basement”. Rapport Grønlands Geologiske Undersøgelse 99 (December). Copenhagen, Denmark:107-10. https://doi.org/10.34194/rapggu.v99.7677.