1. "Report of the Joint ARPA-NASA Committee on Large Clustered Booster Capabilities," 8 Jan. 1959, with endorsement by Hyatt, files of Abraham Hyatt, NASA History Office.
2. "A National Space Vehicle Program," report to the President presented by the National Aeronautics and Space Administration, 27 Jan. 1959, NASA History Office.
3. "Saturn Chronology," ARPA, ca. 1959, accession 68-A-6057, box 1, Federal Records Center, Suitland, MD.
4. Herbert F. York, San Diego, CA, to Eugene M. Emme, NASA, regarding "Saturn Chronology," 10 June 1974.
6. "Saturn Chronology," ARPA, ca. 1959.
7. Telephone interview with James Powell, formerly of Glenn L. Martin Co. and responsible for the Titan C concept, now at the Energy Research and Development Administration, Washington, 17 Sept. 1975.
8. York to Emme, 10 June 1974.
9. "Saturn Chronology," ARPA, ca. 1959.
11. Interview of York by Emme, 12 June 1973.
12. "Saturn Chronology, ARPA, ca. 1959.
13. Ibid.; York to Emme. 10 June 1974.
14. Interview with Richard E. Horner, Washington, 13 Mar. 1974.
15. Wernher von Braun to Monte D. Wright, 29 Dec. 1975.
16. Interviews, Francis L. Williams, NASA, Washington, 11, 26 Mar. 1974.
17. "Project Horizon Report: A U.S. Army Study for the Establishment of a Lunar Outpost, "vol.2, "Technical Considerations and Plans, " 9 June 1959.
18. E. W. Hall to Silverstein, "Proposed Saturn Development Schedule, 23 Oct. 1959, E. W. Hall file, NASA History Office.
19. E. W. Hall, "Report on Technical Suivey of ABMA Activities," 2 Nov. 1959; also incorporated in "Technical Survey of ABMA Activities: Propulsion Development & Saturn Vehicles," A. Hyatt, A.O. Tischler, and E. W. Hall, 10 Nov. 1959. The 30 Oct. meeting at the Pentagon is on Hall's appointment calendar. Hall and Hyatt files, NASA History Office.
20. E. W. Hall, notes titled "Saturn Upper Stage Selection," 3 Nov. 1959, files of Hall, NASA History Office.
21. Homer J. Stewart to Administrator, NASA, "Considerations of Vega, Agena B, and Centaur," 2 Oct. 1959, document IV-1 in "Documents in the History of NASA, An Anthology," HHR-43, NASA History Office.
22. Richard Horner to Herbert York, 9 Nov. 1959, files of F. W. Hall, NASA History Office; Richard Horner, Assoc. Admin., to Abe Silverstein, Dir. of Space Flight Dev., "Establishment of a Saturn Vehicle Team," 7 Nov. 1959, files of E. W. Hall, NASA History Office; "Report to the Administrator, NASA, on NASA Development Plan," by Saturn Vehicle Team, 15 Dec. 1959, NASA History Office. The report, without attachments, is in "Documents in the History of NASA."
23. Comments of Col. N. C. Appold in "Minutes of the Meetings of Saturn Vehicle Team," NASA Hq., Washington, 28 Nov. 1959, files of Eldon W. Hall, NASA History Office.
24. Telephone interview with T. C. Muse, Arlington, VA, 22 Sept. 1975.
25. Wernher von Braun to Monte D. Wright, 29 Dec. 1975.
26. Von Braun to the author, 8 Nov. 1973; von Braun to Wright, 29 Dec. 1975; interview with Krafft Ehricke, 26 Apr. 1974; interview with Richard Canright, 7 Mar. 1974.
27. Interview with Eldon Hall, 28 Feb. 1974.
28. Ibid.; interview with Hyatt, 26 Apr. 1974.
29. Minutes of the meetings of 27, 28 Nov. and 3, 4, 14, and 15 Dec. are in the files of Eldon W. Hall, NASA History Office. Reference is made to meetings of 10, 11 Dec., but no record of minutes has been located. A working copy of the report, dated 10 Dec., is also in Hall's file. The final report, "Report to the Administrator, NASA, on Saturn Development Plan by Saturn Vehicle Team," 15 Dec. 1959, is reprinted without appendices as document IV-7 of "Documents in the History of NASA."
30. Interviews of Francis L. Williams, 7, 11 Mar. 1974.
31. Eldon W. Hall to the author, 14 Dec. 1971; interviews with Hall 28 Feb. 1974, with Abraham Hyatt 26 Apr. 1974, with Alfred Nelson 23 Sept. 1975.
32. "Report to Administrator, NASA, on Saturn Development Plans," 15 Dec. 1959.
33. Interview with Francis C. Schwenk, NASA, Washington, 8 Mar. 1974.
34. Horner to Ostrander and Silverstein, 29 Dec. 1959, E. W. Hall files, NASA History Office.