NASA Astronaut-Signed Philatelic Collection: Complete Set of Twenty "Sieger" Souvenir Sheets. Each of these twenty foreign stamps and blocks were signed between 1968 and 1971 for a German stamp dealer named Herman Sieger. Apollo 7 astronaut Walt Cunningham tells the background in his book, The All-American Boys (MacMillan: New York, 1977): "My own involvement began with a 1969 phone call from Walter Eiermann, whom many of us had met socially in Coco Beach. Eiermann said he was negotiating with many of the astronauts to sign 500... stamps issued to commemorate the individual's flight for a payment of $2,500. My answer was probably common: Yes, I'd be interested if others in the group were doing the same thing. The money was attractive and it wasn't explicitly against any regulation, but I was not interested in becoming a trail blazer. Three months later he called with a list of those who had already committed. His goal was to sign every man who had flown an Apollo mission, and he seemed well on his way." The sets of twenty were originally sold for 1,950 German marks in the early 1970s. Many of the sets have been broken up and sold separately in the intervening years. This is a complete set that includes the original German-language biography cards for each astronaut.