Arnold, F., Pirjola, L., Ronkko, T., Reichl, U., Schlager, H., Lahde, T., Heikkila, J., & Keskinen, J. (2012). First Online Measurements of Sulfuric Acid Gas in Modern Heavy-Duty Diesel Engine Exhaust: Implications for Nanoparticle Formation. Environmental Science & Technology, 46(20), 11227-11234. doi:10.1021/es302432s.