Railroad Archives Online
- ΑρχείοD0036 - George Werkema Collection
- 004 - Northern Pacific Railroad Company
- Υποσειρά014 - Photographs
- 001 - Railroads--Equipment and Supplies
- 003 - Freight Cars
- ΤεκμήριοWerkema103 - Northern Pacific box car 1005 on a yard track in Denver, Colorado.
- ΤεκμήριοWerkema104 - Northern Pacific box car 1125 in March 1975
- ΤεκμήριοWerkema105 - Northern Pacific box car 1160 in Albuquerque, New Mexico in 1978.
- ΤεκμήριοWerkema106 - Northern Pacific box car 1220 in Albuquerque, New Mexico in 1980.
- ΤεκμήριοWerkema107 - Northern Pacific box car 1220 in Albuquerque, New Mexico in 1980.
- ΤεκμήριοWerkema108 - Northern Pacific box car 1229 in Albuquerque, New Mexico in 1978.
- 217 more...