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
- 18 more...
- ItemWingfield.190 - Northern Pacific Diesel Locomotive 3600, 2808, 2527 at Marshall, Washington, 1968
- ItemWingfield.192 - Northern Pacific Diesel Locomotive 3600, 2808, 2527 at Marshall, Washington, 1968
- ItemWingfield.194 - Northern Pacific Diesel Locomotive 3614 at Spokane, Washington, 1968
- ItemWingfield.197 - Northern Pacific Diesel Locomotive 2512, 2510, 3617 at Marshall, Idaho, 1968
- ItemWingfield.198 - Northern Pacific Diesel Locomotive 2512, 2510, 3617 at Marshall, Washington, 1968
- ItemWingfield.199 - Northern Pacific Diesel Locomotive 2515 at Spokane, Washington, 1968
- 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
- 11 more...