Li, W., Collins, J. F., Durbin, T. D., Huai, T., Ayala, A., Full, G., Mazzoleni, C., Nussbaum, N. J., Obrist, D., Zhu, D., Kuhns, H. D., Moosmüller, H. (2007). Detection of Gasoline Vehicles with Gross PM Emissions, SAE Tech. Pap. Ser. SP-2089, 13 pp., SAE International: Warrendale, PA