NASA TT F-622. Ways to spaceflight, by Hermann Oberth (Translation of «Wege zur Raumschiffahrt», R. Oldenbourg Verlag, Munich-Berlin, 1929); 1970. Page 200—201
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WHAT WOULD AN INTERSTELLAR MISSION LOOK LIKE?Архивная копия от 16 октября 2012 на Wayback Machine // Discovery.com, Feb 25, 2011. By Robert Adams (Lead Designer for the Mission Analysis and Performance Module, Project Icarus): «First described by Hermann Oberth in 1927, the two-burn escape maneuver can be very effective for this mission…»
WHAT WOULD AN INTERSTELLAR MISSION LOOK LIKE?Архивная копия от 16 октября 2012 на Wayback Machine // Discovery.com, Feb 25, 2011. By Robert Adams (Lead Designer for the Mission Analysis and Performance Module, Project Icarus): «First described by Hermann Oberth in 1927, the two-burn escape maneuver can be very effective for this mission…»