We express here our grateful appreciation to the many organizations and individuals who have rendered valuable assistance to our study. It is impracticable to list all of the hundreds of members of the general public who have made suggestions or written about their experiences. We apologize if we have overlooked any who should be specially recognized. Those to whom we owe particular thanks are:

National Research Council of Canada, particularly Dr. Peter M. Millman, for detailed information about UFO matters in Canada.

National Aeronautics and Space Administration, which appointed Dr. Urner Liddel as liaison officer to this study, and also for cooperation of the astronauts with Dr. Roach in the preparation of Section III, Chapter 6.

Environmental Science Services Administration, particularly to Dr. George S. Benton and Dr. C. Gordon Little who arranged for us to have the services of Mr. Gordon Thayer in the preparation of Section III, Chapter 5, and for critical review of early drafts of Section VI, Chapter 5; and for general cooperation of the Weather Bureau.

U.S. Naval Observatory, particularly Dr. R. L. Duncombe, director, Nautical Almanac Office, who carried out the perturbation calculations on Clarion mentioned in Section II (p. 42).

Alcohol and Tobacco Tax Division, Internal Revenue Service, particularly Mr. Maynard J. Pro who arranged for the neutron activation analysis of a magnesium sample mentioned in Case 4 (p. 391).

U.S. Forest Service, particularly Mr. C. A. Shields, director of division of administrative management, for information about local areas of forest damage.

Federal Aviation Agency, particularly Mr. Clyde Dubbs, and Mr. Newton Lieurance, for general cooperation of air traffic controllers in relation to UFO reports. (Section III, Chapter 1.)

Library of Congress, particularly Miss Lynn Catoe, for information on published material on UFOs.

U.S. Department of State, for assistance in securing information about the UFO interests of foreign governments (Section V, Chapter 3) particularly Dr. Walter Ramberg, science attache' in Rome, Italy for information for Section V, Chapter 2.

U.S. Air Force, particularly Lt. Col. Robert Hippler and Lt. Col. Hector Quintanilla, and Dr. William Price and Dr. J. Thomas Ratchford of the Air Force Office of Scientific Research, for prompt and efficient responses to our requests for information, and great tact in not influencing the course of the study. Also the UFO officers at all of the various Air Force bases for reports and general cooperation.

The University of Arizona, particularly the Lunar and Planetary Laboratory, for arranging for the study to have the services of Dr. William K. Hartmann who prepared Section III, Chapter 2, and Section IV, Chapter 3. Also the Institute of Atmospheric Physics whose Dr. James E. McDonald gratuitously (sic) supplied information and criticism, especially in regard to UFO matters in Australia, New Zealand and Tasmania, which he studied during a trip there which was sponsored by the U.F. Office of Naval Research.

University of Wyoming, for the assistance of Prof. R. Leo Sprinkle in connection with Case 42 (p. 598).

University of Colorado, (in addition to those on the project staff), to Prof. Ned Bowler, Department of Audiology and Speech Pathology for sonograms of bird calls and other sounds used in study of Case 20 (p. 468); to the School of Medicine, for the services of Dr. Mark Rhine in the preparation of Section VI, Chapter 3; to Dr. William A. Scott, Dr. Thomas O. Mitchell, Mr. Ronnal L. Lee, Dr. David R. Saunders, Miss Dorothy R. Davis and Miss Marilyn R. Bradshaw for contributions to Section III, Chapter 7.

Stanford Research Institute, particularly Dr. R. T. H. Collis, who arranged for the study to have the services of Dr. William Viezee and Dr. Roy H. Blackmer, Jr., in preparation of Section VI, Chapters 4 and 5. Thanks are also due Mr. Roy M. Endlich and Dr. Edward E. Uthe

and also Dr. J. V. Dave of the International Business Machines Corporation of Palo Alto for assistance in this connection.

Smithsonian Astrophysical Observatory, particularly Dr. Fred H. Whipple for the cooperation extended in connection with their Prairie Network, discussed in Section VI, Chapter 9. Also to Dr. Donald H. Menzel for much information and advice based on his long and critical study of UFO matters.

Northwestern University, Dearborn Observatory, for information and consultation voluntarily supplied by Dr. J. Allen Hynek and others on his staff, particularly Dr. Jacques Vallee and Dr. William Powers.

Illinois Institute of Technology Research Institute, for the loan of the all-sky camera used in Case 27 (p. 508)

National Center for Atmospheric Research, and its director, Dr. Walter Orr Roberts, for the services of: Dr. Joseph H. Rush, who consulted on instrumentation problems and critically edited many of the case reports in Section IV; Dr. Vincent Lally in preparing Section VI, Chapter 8; Dr. Paul Julian in preparing Section VI, Chapter 10; Dr. Martin Altschuler in preparing Section VI, Chapter 7; Dr. Julian Shedlovsky, who provided information on radio-activity induced in various materials on exposure to radiation in outer space; and for many consultations on special problems.

Ford Motor Company, particularly to Dr. Michael J. Ference, vice-president for research, Mr. Frederick J. Hooven, now of Dartmouth College, and Mr. David F. Moyer, for assistance on alleged effects of UFOs on automobiles. (Section III, Chapter 4, p. 151; Case 12, p. 432; and Case 39, p. 582.)

Dow Chemical Company, particularly Dr. R. S. Busk and Dr. D. R. Beaman, for information and analyses of a magnesium sample (Case 4, p. 391).

Raytheon Company, Autometrics Division, for the services of Mr. Everitt Merritt in connection with photogrammetric studies. (Section II, p. 50.)

Volunteer Flight Officer Network, and particularly Mr. H. E. Roth, United Airlines, for reports of sightings by commercial air transport pilots (p. 84).

Aerial Phenomena Research Organization, particularly James and Coral Lorenzen, for information and samples particularly referring to South American cases, and for the cooperation of many of its members in supplying prompt notice of UFO sightings to our Early Warning System (Section III, Chapter 1, p. 84).

National Investigations Committee for Aerial Phenomena, particularly Donald Keyhoe and Richard H. Hall, for supplying copies of case reports from NICAP files, and for the cooperation of many of its members in supplying prompt notice of UFO sightings to our Early Warning Network (Section III, Chapter 1, p. 84); and to Raymond E. Fowler of Wenham, Mass., in connection with the study of UFO reports in the New England region.

Ottawa New Sciences Club, particularly Mrs. Carol Halford-Watkins, for information about a metallic mass claimed to have UFO significance.

Mr. Gerard Piel, publisher of the Scientific American for valuable advice on editorial matters and particularly for having helped secure the services of Mr. Daniel S. Gillmor as editor of this report.

Mr. Philip J. Klass, senior editor of Aviation Week and Space Technology, for assistance in connection with atmospheric plasmas in relation to UFO reports, and for helpful information on UFO developments in Washington.

Mr. Philip Wittenberg, member of the New York bar and author of The Protection of Literary Property; Mr. Charles Williams, Mr. Edwin Kahn, Mr. J. Michael Farley, Mr. John Holloway, and the late Mr. Phillip Danielson, members of the Colorado bar, for valuable advice on legal problems related to the study.

Mrs. LaVern Knoll, reference librarian at the Great Falls, Montana, public library, for searching files of Great Falls Leader in connection with Case 47 (p. 626).

Mr. Gary Rosenberger of Boulder, Cob., for use of his automobile and assistance in magnetic measurements involved in Case 38 (p. 582).

American Institute of Public Opinion, for providing the original records of their 1966 po11 on flying saucers, and for permission to use the results in Section III, Chapter 7.

Opinion Research Organization, particularly Leonard F. Newton, Isabelle N. Rhodes and James C. Manuel, who conducted the 1968 study reported in Section III, Chapter 7, under contract with this project.

To the following individuals who assisted in the study of Case 22 (p. 484): Wing Commander D. F. Robertson, Canadian Forces Headquarters; Royal Canadian Air Force Squadron Leader Paul Bissky; Royal Canadian Mounted Police CIB Superintendents G. H. Miller and I. C. Shank, Cpl. G. J. Davis and Constable Zaccherias; Dr. Edward C. Shaw; Director B. C. Cannon and members J. B. Thompson and E. J. Epp of the Canadian Aerian Phenomena Research Organization.

Hauser Research and Engineering Company, Boulder, Colo., for chemical analysis of material identified as chaff in Case 3, p. 388.

Several scientists who gave us useful information on condition that their names would not be mentioned.

And, finally, I would like to add my special thanks to the typists and editorial assistants who handled the monumental task of typing, proofing, correcting, and assembling this report, remaining with the study until its completion: Miss Beth Allman, Miss Ashley Baker, Mrs. Carol Love, Miss Brenda Montalvo and Mrs. Sue Wood. And, above all, to Mrs. Kathryn Shapley, who served loyally and efficiently as my secretary throughout the entire study.