Railroad Archives Online
- CollectionD0011 - James M. Fredrickson Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3001 - Steam locomotives
- 467 more...
- ItemJMF00-00065.0 - Northern Pacific steam locomotive 20 at Billings, Montana, in 1949.
- ItemJMF00-00066.0 - Northern Pacific steam locomotive 20 at Billings, Montana, in 1949.
- ItemJMF00-00067.0 - Northern Pacific steam locomotive 20 at Billings, Montana, in 1953.
- ItemJMF00-00068.0 - Northern Pacific steam locomotive 21 at Billings, Montana, in 1949.
- ItemJMF00-00069.0 - Northern Pacific steam locomotive 21 at Billings, Montana, in 1953.
- ItemJMF00-00069.1 - Northern Pacific steam locomotive 21 at Billings, Montana, circa 1950.
- ItemJMF00-00070.0 - Northern Pacific steam locomotive 23 at Butte, Montana, in 1949.
- ItemJMF00-00071.0 - Northern Pacific steam locomotive 23 at Helena, Montana, in 1952.
- ItemJMF00-00072.0 - Northern Pacific steam locomotive 23 at Helena, Montana, in 1953.
- 2169 more...