[ASTRONAUT SIGNED LETTERS]. ANDERS, WILLIAM. Typed letter signed, Washington, D.C., 28 October 1970, 1 page, 8vo, on National Aeronautics and Space Council letterhead, A thank you for philatelic material sent to him and the fulfillment of an autograph request -- SHEPARD, ALAN. Typed letter signed, Houston, 20 July 1972, 1 page, 8vo, on NASA MSC letterhead, sending regrets that Astronaut Alfred M. Worden can not attend an Explorer's Club speaking engagement -- SLAYTON, DONALD K. Typed letter signed, Houston, 20 January 1976, 1 page, 8vo, on NASA JSC letterhead, sending regrets that he does not have any documents on the Apollo 11 mission. (3)