Operations Directorate Planning Division (November 1990). "Ridership and Service Statistics" (3 ed.). Massachusetts Bay Transportation Authority. pp. 1–4 – via Internet Archive.
Cox, Harold E.; Cummings, O. R. (1963). Surface cars of Boston, 1903-1963. New England Electric Railway Historical Society. hdl:2027/mdp.39015021059525.
"Curiosity Carcards"(PDF). Massachusetts Bay Transportation Authority. Archived from the original(PDF) on February 18, 2017. Retrieved February 21, 2016.
"Subway Map"(PDF). Massachusetts Bay Transportation Authority. 2000. Archived from the original(PDF) on August 17, 2000.
"Subway Map"(PDF). Massachusetts Bay Transportation Authority. 2001. Archived from the original(PDF) on July 1, 2001.
Sanborn, George M. (1992). A Chronicle of the Boston Transit System. Massachusetts Bay Transportation Authority. Archived from the original on November 27, 2019. Retrieved February 21, 2016 – via Massachusetts Institute of Technology.
Howard Needles Tammen & Bergendoff; Thomas K. Dyer Inc. (November 1987). Preliminary Ridership and Cost-Effectiveness Analyses Report(PDF). MBTA Bowdoin/Charles Connector Report: Preliminary Design and Environmental Studies Stats Report. Vol. 2. Massachusetts Bay Transportation Authority. p. PR-13. Archived from the original(PDF) on August 16, 2010.
Sanborn, George M. (1992). A Chronicle of the Boston Transit System. Massachusetts Bay Transportation Authority. Archived from the original on November 27, 2019. Retrieved February 21, 2016 – via Massachusetts Institute of Technology.
"Curiosity Carcards"(PDF). Massachusetts Bay Transportation Authority. Archived from the original(PDF) on February 18, 2017. Retrieved February 21, 2016.
"Subway Map"(PDF). Massachusetts Bay Transportation Authority. 2000. Archived from the original(PDF) on August 17, 2000.
"Subway Map"(PDF). Massachusetts Bay Transportation Authority. 2001. Archived from the original(PDF) on July 1, 2001.
Howard Needles Tammen & Bergendoff; Thomas K. Dyer Inc. (November 1987). Preliminary Ridership and Cost-Effectiveness Analyses Report(PDF). MBTA Bowdoin/Charles Connector Report: Preliminary Design and Environmental Studies Stats Report. Vol. 2. Massachusetts Bay Transportation Authority. p. PR-13. Archived from the original(PDF) on August 16, 2010.