Railroad Archives Online
- CollectionD0063 - Walter W. Ainsworth Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3006 - Cabooses (Railroads)
- ItemJATGCaboose - Great Northern Railway caboose in Washington State, undated.
- ItemJATGCaboose_ALowell - Great Northern Railway caboose in Lowell, Washington, undated.
- ItemJATGCaboose_BInterbay - Great Northern Railway caboose in Interbay, Washington, undated.
- ItemJATGCaboose_X511 - Great Northern Railway caboose X511 in Washington State, undated.
- ItemWWAPC0261 - Great Northern Railway cabooses number X3 and X1 at Seattle, Washington in 1958.
- ItemWWAPC0287 - Great Northern Railway caboose number X1 at Seattle, Washington, circa 1951.
- ItemWWAPC0289 - Great Northern Railway caboose number X1 at Seattle, Washington, circa 1955.
- ItemWWAPC0298 - Great Northern Railway caboose number X1 at Seattle, Washington, circa 1955.
- ItemJATGCaboose_X631 - Great Northern Railway caboose X631 in Washington State, undated.