Railroad Archives Online
- CollectionD0111 - Dan Perkins Collection
- Series003 - Great Northern Railway Company (U.S.) materials
- Subseries Level 1014 - Photographs
- Subseries Level 2001 - Railroads--Equipment and Supplies
- Subseries Level 3002 - Diesel Locomotives
- ItemDRP001-001 - GN #3011 GP30 parked in yard at Mukilteo
- ItemDRP001-010 - GN #697 GP9 parked in GN yard at Spokane