[49] Use-Inheritance. A. & C. Black. Direction of Hair.
[50] Knowledge, January, 1903.
[51] Direction of Hair in Animals and Man.
[52] Op. cit. Use inheritance.
[53] Op. cit. Direction of Hair.
[54] Use-Inheritance.
[55] Direction of Hair in Animals and Man.
[56] Direction of Hair, pp. 88–93.
[57] Contemporary Review, June 1917.
[58] Prehistoric Man and His Story. G. F. Scott Elliott, 1916, pp. 169, 206.