Jelen, M., T. Budkovič, and K. Grad. “Crucisaccites Variosulcatus Djupina from Permian Beds of the Uranium Deposit of Žirovski Vrh”. Geologija, vol. 24, no. 2, Dec. 1981, pp. 319-25, https://www.geologija-revija.si/index.php/geologija/article/view/496.