Kirkham, Lisa, and BCIT School of Health Science, Environmental Health. “Comparisons of the Vehicular Emission Exposure Levels of Respirable Particulate Matter for Three Types of Commuters: Bus, Car and Bicycle”. BCIT Environmental Public Health Journal (April 1, 2008): 31. Accessed May 14, 2024. https://journals.bcit.ca/index.php/ehj/article/view/236.