The human factor in innovation and productivity : hearings (including the record of a seminar sponsored by the American Association for the Advancement of Science on July 28, 1981) before the Subcommittee on Science, Research, and Technology of the Committee on Science and Technology, U.S. House of Representatives, Ninety-seventh Congress, first session, September 9, 10, 11, 15, 16, 17, 1981.