(1) Darwin, Charles. The Descent of Man. Chaps. xvii and xviii. "Secondary Sexual Characters of Mammals," pp. 511-67. (Gives account of the fighting instinct in males and the methods of fighting of animals.) 2d rev. ed. New York, 1907.
(2) Johnson, George E. "The Fighting Instinct: Its Place in Life," Survey, XXXV (1915-16), 243-48.
(3) Thorndike, Edward L. The Original Nature of Man. "Fighting," pp. 68-75. New York, 1913.
(4) Hall, G. Stanley. "A Study of Anger," American Journal of Psychology, X (1898-99), 516-91.
(5) Patrick, G. T. W. The Psychology of Social Reconstruction. Boston, 1920.
(6) ——. The Psychology of Relaxation. Chap. vi, "The Psychology of War," pp. 219-52. Boston, 1916.
(7) Pillsbury, W. B. The Psychology of Nationalism and Internationalism. New York, 1919.
(8) Trotter, W. Instincts of the Herd in Peace and War. London, 1916.
(9) La Grasserie, R. de. "De l'intolerance comme phénomène social," Revue International de Sociologie, XVIII (1910), 76-113.
(10) Percin, Alexandra. Le Combat. Paris, 1914.