• Skvortsova L. N. Ion-exchange removal of Fe(III) and Mg(II) in the analysis of rare earth elements in rocks by inductively coupled plasma mass spectrometry / L. N. Skvortsova, A. S. Podprugin, V. I. Otmakhov // Key engineering materials. 2015. Vol. 670. P. 258-263. URL: http://vital.lib.tsu.ru/vital/access/manager/Repository/vtls:000569140