Dżaluk, Agnieszka, Dariusz Malczewski, Jerzy Żaba, and Maria Dziurowicz. “Laboratory Measurements of Natural Radioactivity in Selected Igneous Rocks of the Opava Mountains Region”.
Geology, Geophysics and Environment 41, no. 1 (August 5, 2015): 73. Accessed March 13, 2025.
https://journals.agh.edu.pl/geol/article/view/1457.