| Event | GWB |
|---|---|
| Narrative | Mount Vernon Postmark #1: Mount Vernon, VA — 1978-02-22 Stamp: Right to Peaceable Assembly, Dome of the Capitol, 9 cents (Scott #1591) |
| Cachet Sponsor | GWMSC |
| Design | Pictorial |
| Scott # | 1591 |
| Stock # | G-78-001 |
| Postmark Type | Std |
| Location | Mount Vernon, VA |
| Owner | GWMSC |