Railroad Archives Online
- FondosE0480 - Great Northern Railway Historical Society Miscellaneous Collection
- Series003 - Great Northern Railway Company (U.S.)
- Sub-series008 - Ephemera
- ItemEMPIRE BUILDER RADIO STORY CONTEST - Empire Builder Radio Story Contest Pamphlet, 1929
- ItemTHE EMPIRE BUILDER RADIO - Advertising Pamphlet for "The Empire Builders", 1929
- ItemWESTWARD TIDE - Radio Show Script for "The Westward Tide", 1929