1. N.E. Kuz’mina, K. K. Palkina, O. V. Koval’chukova, et al., Zh. Neorg. Khim. 47(11), 1843 (2002) [Russ. J. Inorg. Chem. 47 (11), 1693 (2002)].
2. O. V. Koval’chukova, K. K. Palkina, Tran Tkhan Tun, et al., Zh. Neorg. Khim. 52(5) (2007 ) [Russ. J. Inorg. Chem. 52(5), 733(2007)].
3. G. M. Sheldrick, SHELXL 93, Program for the Refinement of Crystal Structures, Germany, Univ. of Göttingen, 1993.
4. O. J. Parker and G. L. Breneman, Acta Crystallogr., Sect. C: Cryst, Struct. Commun. 51, 1097 (1995).
5. C. Näther, M. Wriedt, and I. Jeß, Acta Crystallogr., Sect. E: 58(3), m107 (2002).