USA
Viser nu USA - Luftpostfrimærker (1918 - 2012) - 1 frimærker.
1973
Progress in Electronics
10. juli VM: Ingen Design: Walter y Naiad Einsel. Gravering: Bureau of Engraving & Printing. Perforeringer: 11
![[Progress in Electronics, type BG]](https://www.stampworld.com/media/catalogue/United-States/Airmail-stamps/BG-s.jpg)
