Schuck, T. J., Ishijima, K., Patra, P. K., Baker, A. K., Machida, T., Matsueda, H., et al. (2012). Distribution of methane in the tropical upper troposphere measured by CARIBIC and CONTRAIL aircraft. Journal of Geophysical Research-Atmospheres, 117: D19304. doi:10.1029/2012JD018199.