1. Allen, H. C., jr., Cross, P. C.: Molecular vib-rotors, Kap. 1. und 2. New York-London: J. Wiley & Sons, Inc. 1963
2. Cuthbert, J., Denney, E. J.: Molecular Spectry. 1971, 243?258
3. Cuthbert, J., Denney, E. J., Silk, C., Stratford, R., Farren, J., Jones, T. L., Pooley, D., Webster, R. K., Wells, F. H.: J. Physics E: Sci. Instruments 5, 698 (1972)
4. Cyvin, S. J.: Molecular structures and vibrations, Kap. 12. Amsterdam-New York-London: Elsevier Publ. Co. 1972
5. French, I. P., Arnold, T. E.: Rev. Sci. Instruments 38, 1604 (1967)