1. Robert K. Merton, Social Theory and Social Structure, (re-vised edition), Glencoe: Free Press, 1957, pp. 319-353.Merton319Social Theory and Social Structure1957
2. Robert E. Park, Race and Culture, Glencoe: Free Press,1950, p. 190Park190Race and Culture1950
3. Negro Visibility
4. Robin M. Williams, Jr., The Reduction of IntergroupTensions, New York: Social Science Research Council, 1947, p. 54Williams54The Reduction of Intergroup Tensions1947
5. William M. Kephart, Racial Factors and Urban Law Enforcement,Philadelphia: University of Pennsylvania Press, 1957, pp. 100-102Kephart100Racial Factors and Urban Law Enforcement1957