J. Deniker: _The Races of Man_, etc., New York, 1904.
*J. Finot: _Race Prejudice_ (tr. by Wade-Evans), New York, 1907.
*W.Z. Ripley: _The Races of Europe_, etc., New York, 1899.
*Jacques Loeb: in _The Crisis_, Vol. VIII, p. 84, Vol. IX, p. 92.
*_Papers on Inter-Racial Problems Communicated to the First Universal
Races Congress_, etc. (ed. by G. Spiller), 1911.
*G. Sergi: _The Mediterranean Race_, etc., London, 1901.
*Franz Boas: _The Mind of Primitive Man_, New York, 1911.
C.B. Davenport: _Heredity of Skin Color in Negro-White Crosses_, 1913.