Sugawara et al., Aircraft measurements of the stable carbon isotopic ratio of atmospheric methane over Siberia, Global Biogeochem. Cycles, 10, 223-231, 1996.
Sugawara et al., Reconstruction of past variations of d13C in atmospheric CO2 from its vertical distribution observed in the firn at Dome Fuji, Antarctica, Tellus, 55, 159- 69, 2003. |