Sensitive detection of methane and nitrous oxide isotopomers using a continuous wave quantum cascade laserG. Gagliardi, F. Tamassia, P. De Natale, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson and A. Y. ChoEur. Phys. J. D, 19 3 (2002) 327-331DOI: https://doi.org/10.1140/epjd/e20020091