Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910: The New York Tunnel Extension of the Pennsylvania Railroad,; The North River Division. Paper No. 1151 | Digital Library | PAMCET

Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910: The New York Tunnel Extension of the Pennsylvania Railroad,; The North River Division. Paper No. 1151 | Digital Library | PAMCET | PAMCET