1. Devyatykh, G.G., Karpov, Yu.A., and Osipova, L.I., Vystavka-kollektsiya veshchestv osoboi chistoty (Exhibition–Collection of Extrapure Substances), Moscow: Nauka, 2003.
2. Karpov, Yu.A., Churbanov, M.F., Baranovskaya, V.B., Lazukina, O.P., and Petrova, K.V., High purity substances – prototypes of elements of Periodic Table, Pure Appl. Chem., 2020, vol. 92, no. 8, pp. 1357–1366. https://doi.org/10.1515/pac-2019-1205
3. Malyshev, K.K., Lazukina, O.P., Volkova, E.N., and Churbanov, M.F., A new technique for estimating the average and total impurity concentrations in samples of high-purity substances, Inorg. Mater., 2016, vol. 52, no. 3, pp. 313–323.
4. Lazukina, O.P., Malyshev, K.K., Volkova, E.N., and Churbanov, M.F., Impurity composition of high-purity solid halides, Inorg. Mater., 2019, vol. 55, no. 12, pp. 1273–1284.
5. Zelenskii, V.F., Tikhinskii, G.F., and Azhazha, V.M., Preparation and some properties of extrapure rare and rare-earth metals, Vysokochist. Veshchestva, 1994, no. 3, pp. 66–75.