Railroad Archives Online
- CollectionD0036 - George Werkema Collection
- Series003 - Great Northern Railway Company (U.S.)
- Subseries Level 1014 - Photographs
- Subseries Level 2003 - Railroads--Buildings and Structures
- Subseries Level 3003 - Maintenance Facilities
- Itemimg1129 - Great Northern Roundhouse at Whitefish, Montana, 1990
- Itemimg1130 - Great Northern Roundhouse at Whitefish, Montana, 1990
- Itemimg1131 - Great Northern Roundhouse at Whitefish, Montana, 1990
- Itemimg1132 - Great Northern Roundhouse at Whitefish, Montana, 1990
- Itemimg1136 - Great Northern Shop at Interbay, Washington, 1982
- 8 more...