Huang, L., Chivulescu, A., Allison, C., Brailsford, G., Brand, W. A., Wendeberg, M., Bollenbacher, A., Keeling, R., Levin, I., Sabasch, M., Leuenberger, M., Mukai, H., Nakazawa, T., Aoki, S., Neubert, R., Aerts-Bijma, A., Verkouteren, M., White, J., Vaughn, B., Michel, S., Zhou, L., & Liu, L. (2011). A Report of δ13C & δ18O Measurements in NBS 19 and NBS 18 pure CO2: Uncertainty in Traceability of CO2 Isotope Measurements. In 15th IAEA/WMO meeting of CO2 experts.