Central Transportation Planning Staff (January 2004) [May 2003]. "Chapter 5C: Service Expansion"(PDF). 2004 Program for Mass Transportation. Boston Metropolitan Planning Organization. Archived from the original(PDF) on 20 February 2012. Retrieved 17 July 2012.
"Take the T to Ski!"(PDF). TRANSReport. Boston Region Metropolitan Planning Organization. December 2006. Archived from the original(PDF) on 16 January 2011.
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Weingroff, Richard F. (July–August 2013). "Busting the Trust". Public Roads. 77 (1). Federal Highway Administration. Retrieved 17 January 2014.
Peterson, Scott (26 December 2004). "Appendix D: CTPS Documentation"(PDF). Fitchburg Commuter Rail Line Service Expansion Study. Massachusetts Bay Transportation Authority. Archived from the original(PDF) on 18 March 2006. Retrieved 19 January 2014.
"Appendix E: Cost Estimates"(PDF). Fitchburg Commuter Rail Line Service Expansion Study. Massachusetts Bay Transportation Authority. 26 December 2004. Archived from the original(PDF) on 18 March 2006. Retrieved 20 January 2014.
"Take the T to Ski!"(PDF). TRANSReport. Boston Region Metropolitan Planning Organization. December 2006. Archived from the original(PDF) on 16 January 2011.
Peterson, Scott (26 December 2004). "Appendix D: CTPS Documentation"(PDF). Fitchburg Commuter Rail Line Service Expansion Study. Massachusetts Bay Transportation Authority. Archived from the original(PDF) on 18 March 2006. Retrieved 19 January 2014.
Central Transportation Planning Staff (January 2004) [May 2003]. "Chapter 5C: Service Expansion"(PDF). 2004 Program for Mass Transportation. Boston Metropolitan Planning Organization. Archived from the original(PDF) on 20 February 2012. Retrieved 17 July 2012.
"Appendix E: Cost Estimates"(PDF). Fitchburg Commuter Rail Line Service Expansion Study. Massachusetts Bay Transportation Authority. 26 December 2004. Archived from the original(PDF) on 18 March 2006. Retrieved 20 January 2014.