Kissabekova А., Krasnikov А., Assylbayev Р., and Baubekova Г. “Cathodoluminescence Characteristics of Bismuth-Doped Lanthanide Niobates”. BULLETIN OF THE L.N. GUMILYOV EURASIAN NATIONAL UNIVERSITY. PHYSICS. ASTRONOMY SERIES, vol. 149, no. 4, Dec. 2024, pp. 100-14, https://bulphysast.enu.kz/index.php/physast/article/view/373.