1. American Petroleum Institute, 2015. Diesel Tax, February 6, 2015. Available at 〈http://www.api.org/oil-and-natural-gas-overview/industry-economics/fuel-taxes/diesel-tax〉.
2. Cost-benefit Analysis;Boardman,2014
3. Bureau of Labor Statistics. Occupational Outlook Handbook: School Bus driver salary, February 13, 2015. Available at: 〈http://www.bls.gov/ooh/transportation-and-material-moving/bus-drivers.htm〉.
4. Chandler, K., Walkowicz, K., 2006. King County Metro Transit Hybrid Articulated Buses: Final Evaluation Report. National Renewable Energy Laboratory, NREL/TP-540-40585. Available at 〈http://www.nrel.gov/docs/fy07osti/40585.pdf〉.
5. Clark, N., Zhen, F., Wayne, S., Lyons, D., 2007. Transit Bus Life Cycle Cost and Year 2007 Emissions Estimate. Federal Transit Administration. Washington, DC. Available at: 〈http://www.fta.dot.gov/documents/WVU_FTA_LCC_Final_Report_07-23-2007.pdf〉.