{{Executive Summary(PDF). Program of Mass Transportation. Boston Regional Metropolitan Planning Organization: ES-8. January 2004. (原始内容(PDF)存档于February 20, 2012).
Sanborn, George M. A Chronicle of the Boston Transit System. Massachusetts Bay Transportation Authority. 1992 [2019-10-18]. (原始内容存档于2015-08-18) –通过Massachusetts Institute of Technology.
Sanborn, George M. A Chronicle of the Boston Transit System. Massachusetts Bay Transportation Authority. 1992 [2019-10-18]. (原始内容存档于2015-08-18) –通过Massachusetts Institute of Technology.
{{Executive Summary(PDF). Program of Mass Transportation. Boston Regional Metropolitan Planning Organization: ES-8. January 2004. (原始内容(PDF)存档于February 20, 2012).