1. Naumov, A.V. and Naumova, M.A., Tsvetn. Met., 2010, no. 10, p. 6.
2. Soshnikova, L.A. and Ezernitskaya, M.E., Tsvetn. Met., 1962, no. 7, p. 60.
3. Ashikhin, V.V. Refining the Crude Lead in Chloride Melts, Extended Abstract of Cand. Sci. (Eng.) Dissertation, Ekaterinburg: UGTU–UPI (Ural Gos. Tekh. Univ.–Ural Polytekh. Inst.), 2009.
4. Alikperov, A.I., Efendiev, G.Kh., and Rustamov, P.G., USSR Inventor’s Certificate No. 165 544, 1963.
5. Lebedev, V.A., Dokl. Akad. Nauk, 1993, vol. 330, no. 5, p. 586.