Rujukan Orbit geopegun

  1. ↑ Noordung, Hermann (1929). Das Problem der Befahrung des Weltraums: Der Raketen-Motor (PDF). Berlin: Richard Carl Schmidt & Co. m/s. 98–100.
  2. ↑ "(Korvus's message is sent) to a small, squat building at the outskirts of Northern Landing. It was hurled at the sky. ... It ... arrived at the relay station tired and worn, ... when it reached a space station only five hundred miles above the city of North Landing." Smith, George O. (1976). The Complete Venus Equilateral. New York: Ballantine Books. m/s. 3–4. ISBN 978-0-345-28953-7.
  3. ↑ "It is therefore quite possible that these stories influenced me subconsciously when ... I worked out the principles of synchronous communications satellites ...", McAleer, Neil (1992). Arthur C. Clarke. Contemporary Books. m/s. 54. ISBN 978-0-809-24324-2.
  4. ↑ Arthur C. Clarke (October 1945). "Extraterrestrial Relays: Can Rocket Stations Give World-wide Radio Coverage?" (PDF). Arthur C. Clarke Institute for Space Education. Dicapai pada 1 January 2021.