The Dual System of Rapid Transit. New York State Public Service Commission. September 1912. Archived from the original on September 25, 2019. Retrieved September 12, 2019 – via nycsubway.org.
Linder, Bernard (September 1988). "Pelham Bay Line". New York Division Bulletin. 31 (9). Electric Railroaders' Association: 2–7. Archived from the original on September 20, 2019. Retrieved September 12, 2019.
The Dual System of Rapid Transit. New York State Public Service Commission. September 1912. Archived from the original on September 25, 2019. Retrieved September 12, 2019 – via nycsubway.org.
Linder, Bernard (September 1988). "Pelham Bay Line". New York Division Bulletin. 31 (9). Electric Railroaders' Association: 2–7. Archived from the original on September 20, 2019. Retrieved September 12, 2019.