Acknowledgments are due the following for permission to quote copyrighted material: The American Institute for Research; The American Personnel and Guidance Association; The American Psychological Association; The American Sociological Society; Duke University Press; Educational and Psychological Measurement; Harcourt, Brace & Co.; Harper & Bros.; Houghton Mifflin Co.; Howard University Press; The Journal Press; Kegan Paul, Trench, Trubner. and Co.; Alfred A. Knopf; The National Academy of Sciences; The National Opinion Research Center; Opinion Research Corporation; Princeton University Press; Science Research Associates; The Scientific American; The Scientific Monthly; Stanford University Press; University of Chicago Press; University of Minnesota Press; Warwick and York; John Wiley & Sons.
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