Jeffrey L. "At the Threshold of Space." Air and Space magazine, October/November 1993. Evans, Alun. Brassey's Guide to War Films. Dulles, Virginia: Potomac Books, 2000. . Finn, Margaret L. Mary Tyler Moore. New York: Chelsea House, 1996. . Godwin, Robert, ed. X-15: The NASA Mission Reports. Burlington, Ontario: Apogee Books, 2001. . Hardwick, Jack and Ed Schnepf. "A Buff's Guide to Aviation Movies". Air Progress Aviation, Vol. 7, No. 1, Spring 1983. Parish, James Robert, Don E. Stanke and Michael R. Pitts. The All-Americans. New Rochelle, New York: Arlington House, 1977. . Thompson, Milton O. At the Edge of Space: The X-15 Flight Program. Washington, D.C.: Smithsonian Books, 1992. . Von Gunden, Kenneth. Flights of Fancy: The Great Fantasy Films. Jefferson, North Carolina: McFarland & Company, 1989. . External links 1961 films 1961 drama films 1961 directorial debut films 1960s American films American aviation films American drama films 1960s English-language films Films about astronauts Films about test pilots Films about the United States Air Force Films directed by Richard Donner Films scored by Nathan Scott United Artists films