1. A Summary. R. Robinson. Journal of the Society of Dyers and colourists, Jubilee issue, 1934, Page 65.
2. Proceedings og the Royal Society, 1931, vol. 133A, Page 668
3. “Physikalische Chemische Tabellen” Landolt-Börnstein (1923), and supplements (1927), 91931), and (1935) were referred to for the numerical value of K, except in the cases of the more recent determinations marked.