| Title | Keystone Publishing Company. Letter |
| Genre | Letters (correspondence) |
| Form | correspondence |
| Call Number | ave_biggert_01427 |
| Date | 1909 |
| DOI | 10.7916/D8ZW2Z1G |
| Companies | Keystone Publishing Company |
| Collector | Biggert, Robert |
| Current Location | Avery Architectural & Fine Arts Library, Columbia University |
| IIIF Manifest |  |
| Locations | Philadelphia, Pennsylvania, United Statesadd_location |