Georg Gerland, Das Aussterben der Naturvölker; F. Ratzel, Anthropogeographie, vol. ii, pp. 330 et seq.
Page [14].
1. Henry Barth, Travels and Discoveries in North and Central Africa (2d ed., London, 1857-1858), vol. ii, pp. 253 et seq.; vol. iii, pp. 425 et seq., 528 et seq.; vol. iv, pp. 406 et seq., 579 et seq.
2. Gustav Nachtigal, Sahărâ und Sûdân, vol. ii, pp. 391 et seq., 691 et seq.; vol. iii, pp. 270 et seq., 355 et seq.
Page [16].
Mary White Ovington, Half a Man, the Status of the Negro in New York (New York, Longmans, Green, and Co., 1911).
Page [18].
1. Robert Bennett Bean, “On a Racial Peculiarity in the Brain of the Negro” (American Journal of Anatomy, vol. iv [1905]).
2. Fr. P. Mall, “On Several Anatomical Characters of the Human Brain, said to vary according to Race and Sex, etc.” (Ibid., vol. ix, pp. 1-32).
Page [21].