Project Horizon Colonization of the Moon Project A119 Zvezda (moonbase) Space Systems Division, Air Force Systems Command, Lunar Expedition Plan, May 1961 Lunex at Astronautix.com Projekt "Lunex" (in German)
Horizon Колонизация Луны Проект А119 Звезда (лунная база) Space Systems Division, Air Force Systems Command, Lunar Expedition Plan, May 1961 Lunex at Astronautix.com Projekt «Lunex» (in German)