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NOTICE: This volume was produced as part of a project approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. It is a result of work done by the Committee on Science, Engineering, and Public Policy (COSEPUP) as augmented, which has authorized its release to the public. This report has been reviewed by a group other than the authors according to procedures approved by COSEPUP and the Report Review Committee.

Financial Support: The development of this guide was supported by the Arthur L. Day Fund of the National Academy of Sciences. Support for the dissemination of this guide was provided by the Burroughs Wellcome Fund, Shell Oil Company Foundation, Glaxo Wellcome Inc., Bristol-Myers Squibb Pharmaceutical Research Institute, Philips Research, and the following disciplinary societies: American Chemical Society, American Institute of Physics, American Mathematical Society, Society for Industrial and Applied Mathematics, American Sociological Association, American Association of Medical Colleges, American Psychological Association, American Geophysical Union, Geological Society of America, American Society for Cell Biology, American Astronomical Society, National Consortium for Graduate Degrees for Minorities in Science and Engineering, American Geological Institute, Sigma Xi, the Federation of American Societies for Experimental Biology, the American Society for Microbiology, the American Institute for Biological Sciences, and the American Physical Society.

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Copyright 1996 by the National Academy of Sciences. All rights reserved. This document may be reproduced solely for educational purposes without the written permission of the National Academy of Sciences.

Cover illustration by Leigh Coriale.

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