Railroad Archives Online
- CollectionD0011 - James M. Fredrickson Collection
- Series001 - Burlington Northern Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3005 - Maintenance of Way cars
- ItemJMF17-12860.0 - Burlington Northern snow plow 972503 at Minneapolis, Minnesota in 1973.
- ItemJMF17-12830.0 - Burlington Northern maintenance of way D253 at Seattle, Washington in 1973.