"Report to the Mayor of London"(PDF). The Greater London (Central Zone): Congestion Charging Order 2001. Transport for London. February 2002. Archived from the original(PDF) on 28 February 2008. Retrieved 24 January 2008.
"Report to the Mayor of London"(PDF). The Greater London (Central Zone): Congestion Charging Order 2001. Transport for London. February 2002. Archived from the original(PDF) on 28 February 2008. Retrieved 24 January 2008.