Railroad Archives Online
- CollectionD0153 - Doug Wingfield Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3002 - Diesel Locomotives
- 24 more...
- ItemWingfield.200 - Northern Pacific Diesel Locomotive 2520, 3628, 2505 at Marshall, Washington, 1968
- ItemWingfield.201 - Northern Pacific Diesel Locomotive 2520, 3628, 2505 at Marshall, Washington, 1968
- ItemWingfield.202 - Northern Pacific Diesel Locomotive 2525, 2800, 3612 at Spokane, Washington, 1968
- ItemWingfield.203 - Northern Pacific Diesel Locomotive 2525, 2800, 3612 at Spokane, Washington, 1968
- ItemWingfield.204 - Northern Pacific Diesel Locomotive 2528, 3612, 2508 at Marshall, Washington, 1968
- ItemWingfield.205 - Northern Pacific Diesel Locomotive 2529 at Spokane, Washington, 1968
- ItemWingfield.206 - Northern Pacific Diesel Locomotive 2529, 868 at Spokane, Washington, 1968
- ItemWingfield.207 - Northern Pacific Diesel Locomotive 2529, 868 at Spokane, Washington, 1968
- ItemWingfield.208 - Northern Pacific Diesel Locomotive 2804, 2808, 2503 at Marshall, Washington, 1968
- 5 more...