OCLC 49777633 –通过Google Books (英语). M'Adoo Tubes Now Reach 33rd Street; First Through Train from the Downtown Terminal to New One in the Shopping Belt.
Fitzherbert, Anthony. "The Public Be Pleased: William G. McAdoo and the HudsonTubes", Electric Railroaders Association, 1964. 存档副本 (PDF). [2009-03-14]. (原始内容