1. V. Ya. Rosolovsky, Chemistry of anhydrous perchloric acid., Nauka, Moscow (1966), p. 54, p. 60.
2. G. Masherpa, Rev. Chim. Miner., 2, 379–433 (1965).
3. I. Olovsson, J. Chem. Phys., 49, No. 3, 1063–1067 (1968).
4. A. I. Karelin and Z. K. Nikitina, Russ. J. Inorg. Chem., 51, No. 11, 1805–1810 (2006).
5. A. I. Karelin and Z. K. Nikitina., J. Struct. Chem., 56, No. 2 (2015).