provided to allow stratifying
the data according to the gender of the father/mother and son/daughter.
</p>


<h3>Source</h3>

<p>Pearson, K. and Lee, A. (1896). Mathematical contributions to the theory
of evolution. On telegony in man, etc. <em>Proceedings of the Royal Society of
London</em>, 60 , 273-283.
</p>
<p>Pearson, K. and Lee, A. (1903). 
On the laws of inheritance in man: I. Inheritance of physical characters. <em>Biometrika</em>, 2(4), 357-462.
(Tables XXII, p. 415; XXV, p. 417; XXVIII, p. 419 and