작품 상세

Two great covers that have been hand signed by William Bradford Shockley who was an American applied physicist. William B. Shockley was one of three scientists that were jointly awarded the 1956 Nobel Prize in Physics "for their researches on semiconductors and their discovery of the transistor effect." There is a First Day of Issue 100th Anniversary of Thomas Edison commemorative cover with the cancellation stamp dated February 11, 1947 and a National Air and Space Museum for the commemoration of the First Passive Communications Satellite 'Echo 1' cover. Both covers are in very good condition with some light edge and handling wear.