1. W. N. Baer(1933 ), The Economic Development of the Cigar Industry in the United States, Lancaster, Pa.
2. H. G. Barnett(1953 ), Innovation: The Basis of Cultural Change, New York.
3. Th.C. Bleoen(1955 ), Land of Their Choice, St. Paul, Minn. Edgerton Independent, 9 June, 1955 (Newspaper).
4. L. Fostinger(1957 ), A Theory of Cognitive Dissonance, Evanston, Ill.