1. Haynes B D, Mcmanus J L, Duellman J M, Clark D F, Quincy R B, U.S. Patent 6, 613, 268 B2. (2003).
2. Rao R S, Shambaugh R L: Industrial & Engineering Chemistry Research, Vol. 32 (1993) No. 12, p.3100.
3. Marla V T, Shambaugh R L: Industrial & Engineering Chemistry Research, Vol. 42 (2003), No. 26, p.6993.
4. Sun Y, Zeng Y C, Wang X H: Industrial & Engineering Chemistry Research, Vol. 50 (2011), No. 2, p.1109.
5. Uyttendaele M A J, Shambaugh R L: Industrial & Engineering Chemistry Research, Vol. 28 (1989), No. 11, p.1735.