De Palma, André; Lindsey, Robin (2011). "Traffic congestion pricing methodologies and technologies". Transportation Research Part C: Emerging Technologies. 19 (6): 1377–1399. Bibcode:2011TRPC...19.1377D. doi:10.1016/j.trc.2011.02.010.
dot.gov
standards.its.dot.gov
"DSRC Standards: What's New?". ITS Standards Advisory number 3. US Department of Transportation. April 2003. Archived from the original on February 16, 2013. Retrieved September 9, 2013.
De Palma, André; Lindsey, Robin (2011). "Traffic congestion pricing methodologies and technologies". Transportation Research Part C: Emerging Technologies. 19 (6): 1377–1399. Bibcode:2011TRPC...19.1377D. doi:10.1016/j.trc.2011.02.010.
web.archive.org
"DSRC Standards: What's New?". ITS Standards Advisory number 3. US Department of Transportation. April 2003. Archived from the original on February 16, 2013. Retrieved September 9, 2013.