Snow, E. C., On the Intensity of Natural Selection in Man, London, 1911.

Biometrika, Vol. X, pp. 488-506, London, May, 1915.

Pearson, Karl, Tuberculosis, Heredity and Environment, London, 1912. Among the most careful contributions to the problem of tuberculosis are those of Charles Goring (On the Inheritance of the Diathesis of Phthisis and Insanity, London, 1910), Ernest G. Pope (A Second Study of the Statistics of Pulmonary Tuberculosis, London, Dulau & Co.), and W. P. Elderton and S. J. Perry (A Third Study of the Statistics of Pulmonary Tuberculosis. The Mortality of the Tuberculous and Sanatorium Treatment), London, 1909. See also our discussion in Chapter I.