(a) ``Statistical Abstract of the United States 1973,'' U.S. Dept. of Commerce, pp. 181-185, 192.
(b) ``Human Engineering Guide for Equipment Designers,'' Woodson and Conover, pp. 2-166 through 2-169 published by the University of California Press, 2223 Fulton St., Berkeley, California 94720.
(c) ``Human Engineering Guide to Equipment Design,'' Van Cott and KinKade, published by U.S. Dept. of Defense, 1972, Library of Congress Card No. 72-600054, pp. 457-465.
(d) ``The Measure of Man--Human Factors in Design,'' by Henry Dreyfuss, published by Watson-Guptill Publications, Inc., 1 Astor Plaza, New York, New York, 10036.
(e) ``Medical Tribune'', Wed., 8/15/73, p. 21.
(f) ``Technical Rationale in Support of A Safety Standard for Swimming Pool Slides,'' 5/30/75. National Swimming Pool Institute, 2000 K Street NW., Washington, D.C. 20006.