Kurešević, Lidja, and Snežana Dević. 2015. “Mineralogical and Geochemical Characterization of Silica-Carbonate Gemstone Veins from Gaj-Lazine (central Serbia)”. Geologica Macedonica 29 (2), pp. 177-182. https://js.ugd.edu.mk/index.php/GEOLMAC/article/view/1227.