United States
Now showing: United States - Airmail stamps (1918 - 2012) - 2 stamps.
1991
William T.Piper
17. May WM: None Perforation: 11
![[William T.Piper, type CW]](https://www.stampworld.com/media/catalogue/United-States/Airmail-stamps/CW-s.jpg)
1993
William T. Piper - Hair Touches Top Edge of Design
13. July WM: None Perforation: 11¼
![[William T. Piper - Hair Touches Top Edge of Design, type CW1]](https://www.stampworld.com/media/catalogue/United-States/Airmail-stamps/CW1-s.jpg)
