Sources of particulate matter in the northeastern United States in summer: 1. Direct emissions and secondary formation of organic matter in urban plumes.

de Gouw, J.A.; Brock, C.A.; Atlas, E.L.; Bates, T.S.; Fehsenfeld, F.C.; Goldan, P.D.; Holloway, J.S.; Kuster, W.C.; Lerner, B.M.; Matthew, B.M.; Middlebrook, A.M.; Onasch, T.B.; Peltier, R.E.; Quinn, P.K.; Senff, C.J.; Stohl, A.; Sullivan, A.P.; Trainer, M.; Warneke, C.; Weber, R.J.; Williams, E.J.