Walter Brattain John Bardeen William Shockley signed FDC Invented Transistor

Description

1973 first day cover for the "Progress in Electronics" commemorative stamp, hand autographed by Walter Brattain (1902-1987), John Bardeen (1908-1991), and William Shockley (1910-1989), who together in 1947 invented the point-contact transistor and shared the Nobel Prize in Physics in 1956 for their invention.
A COA from Hudson Valley Autograph that offers a lifetime money back guarantee as to the authenticity of this autograph accompanies this item. The seller has been in the autograph industry since 1974, personally acquiring the items in these listings.