Black carbon over Mexico: the effect of atmospheric transport on mixing state, mass absorption cross-section, and BC/CO ratios oleh R. Subramanian, G. L. Kok, D. Baumgardner, A. Clarke, Y. Shinozuka, T. L. Campos, C. G. Heizer, B. B. Stephens, B. de Foy, P. B. Voss, R. A. Zaveri