1. R.S. McDonald, P.A. Wilks Jr., Appl. Spectrosc. 42, 151 (1998)
2. Infrared Raman Users’ Group website, http://www.irug.org/
3. B.A. Price, B. Pretzel, S.Q. Lomax, C. Davis, J.H. Carlson, Revised JCAMP-DX spectral file format for submissions to the infrared Raman Users Group (IRUG) spectral database, available from [2]
4. E.D. Palik, Handbook of Optical Constants of Solids (Academic, New York, 1997)
5. C. Karr Jr., J.J. Kovach, Far-infrared spectroscopy of minerals and inorganics. Appl. Spectrosc. 23, 219–223 (1969)