Leary, Thomas E.; Healey, John R.; Sholes, Elizabeth C. (1991). "Concrete-Central Elevator"(PDF). Historic American Engineering Record. Washington, D.C.: Library of Congress. Archived from the original(PDF) on 2014-04-24. Retrieved April 24, 2014.
Leary, Thomas E.; Healey, John R.; Sholes, Elizabeth C. (1991). "Concrete-Central Elevator"(PDF). Historic American Engineering Record. Washington, D.C.: Library of Congress. Archived from the original(PDF) on 2014-04-24. Retrieved April 24, 2014.