Dolenec, Tadej, and Bogomir Jelen. “Application of Stable Isotope Analyses in Paleobiological Studies of Karnian Bivalves from Lesno Brdo”. Geologija, vol. 30, no. 1, Dec. 1987, pp. 219-30, https://www.geologija-revija.si/index.php/geologija/article/view/592.