Railroad Archives Online
- CollectionD0059 - David Emerson Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3006 - Cabooses (Railroads)
- ItemDEGN201314066 - Great Northern Caboose X580 at Burlington, Washington 1938
- ItemDEGN201314071 - Great Northern Caboose X736 at Burlington, Washington, undated