Behind the flying saucers / F. Scully Vliegmechanica van raketten en ruimtevoertuigen : bewerkt naar het college van prof. ir. H. Wittenberg / A.P. Blom : Dl. 2: Satellieten en ruimtevoertuigen ESTEC : European space research and technology centre / ESA, European space agency defense space interests Hearings before the committee on science and astronautic U.S. House of Representatives 87th congress, 1st Session, 17 - 23 march 1961 national meteorological satellite program Hearings before the Committee on Science and Astronautics U.S. House of Representatives 87th Congress first session, 25-27 july 1961 Kosmos en mens / J.M.J. Kooy agard conference proceedings Effects of atmospheric acoustic gravity waves on electromagnetic wave propagation : papers and discussions presented at the Specialist Meeting of the Electromagnetic Wave Propagation Panel … agard conference proceedings Automation in manned aerospace systems Mensen in het wereldruim : raketten, kunstmanen, ruimtevaart / Hermann Oberth ; [vert. uit het Duits van J.C.P. Stuy ; met een inl. van Wilhelm … report on unidentified flying objects / E.J. Ruppelt Proceedings of a Conference on results of the first U.S. manned suborbital space flight, June 6, 1961, U.S. department of state auditorium / National Aeronautics … Sternenkriege" : Illusionen und Gefahren
