Technical Paper No. 11
PAN AMERICAN HEALTH ORGANIZATION
Pan American Sanitary Bureau
Regional Office of the WORLD HEALTH ORGANIZATION
525 Twenty-third Street, N.W.
Washington, DC, 20037, USA
Publications in PAHO's Technical Paper Series are intended to make generally available material that for economic, technical. or other reasons cannot be included in the Organization's regular publications program and would otherwise receive only limited distribution. They are usually reproduced by photo-offset from typescript, rather than by letterpress, and do not necessarily receive such detailed editorial revision as other PAHO publications.
ISBN 92 75 13011 6
© Pan American Health Organization, 1987
Publications of the Pan American Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Convention. For rights of reproduction or translation of PAHO publications, in part or in toto, application should be made to the Editorial Service, Pan American Health Organization, Washington, D.C. The Pan American Health Organization welcomes such applications.
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