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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council and by competent members of the Chinese Academy of Sciences and the Indian National Science Academy. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This study was supported by Grant No. 95-31825A-POP/PCE and 96-41812A-WER between the National Academy of Sciences and John D. and Catherine T. MacArthur Foundation and Task Order #34, NO1-OD-4139 of the Department of Health and Human Services. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the organizations or agencies that provided support for the project.
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