TY - RPRT TI - Trace gas absorption spectroscopy using laser difference-frequency spectrometer for environmental application AU - Chen, W. AU - Cazier, F. AU - Boucher, D. AU - Tittel, F. K. AU - Davies, P. B. PY - 2001 UR - https://ntrs.nasa.gov/citations/20040088204 ID - 20040088204 ER -