1. See http://www.figarosensor.com.
2. Laser Raman sensor for measurement of trace-hydrogen gas
3. see http://www.spectral.com/raman.htm.
4. Laser Monitoring of the Atmosphere, E. D. Hinkley , Ed., Springer-Verlag, Berlin (1976).
5. Air Monitoring by Spectroscopic Techniques, M. W. Sigrist , Ed., John Wiley and Sons, New York (1994).