@article{CTT100544637,
  author = {K. Tsuji and S. Fujikawa and K. Yamada and N. Yoshida and K. Yamamoto and T. Kikugawa},
  title = {Precise Measurement of the <sup>13</sup>CH<sub>4</sub>/<sup>12</sup>CH<sub>4</sub> Ratio of Diluted Methane Using a Near-Infrared Laser Absorption Spectrometer},
  journal = {Sensors and Actuators B: Chemical},
  year = 2006,
}

@inproceedings{CTT100544657,
  author = {S. FUJIKAWA and K. TSUJI and K. YAMAMOTO and K. UEHARA and T. KIKUGAWA and N. YOSHIDA},
  title = {Carbon isotope analysis of methane by new laser-spectroscopic method},
  booktitle = {Proceedings of Annual Meeting of the Geochemical Society of Japan 2001},
  year = 2001,
}