Group of 8 Olympic postcards including a signed autograph from Adolph Gustav Kiefer (June, 27, 1918 – May 5, 2017) was an American competition swimmer, Olympic competitor, the last surviving gold medalist of the 1936 Summer Olympics and former world record-holder. He was the first man in the world to swim the 100-yard backstroke in under one minute. Kiefer was also an inventor and innovator of new products related to aquatics competition.