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International Cooperation in space
Frutkin, Arnold Wolfe, (1965)
Outer space : prospects for man and society
Bloomfield, Lincoln Palmer, (1968)
Osvoenie kosmičeskogo prostranstva v SSSR 1975 : kosmos - nauke i narodnomu chozjajstvu : po materialam pečati
Štern, M. I., (1977)