Spatial and temporal variability of particulate polycyclic aromatic hydrocarbons in Mexico City. - Thornhill, D. A.; de Foy, B.; Herndon, S. C.; Onasch, T. B.; Wood, E. C.; Zavala, M.; Molina, L. T.; Gaffney, J. S.; Marley, N. A.; Marr, L. C. (Atmospheric Chemistry & Physics, 2008)