1. Svedberg, "General Discussion on Colloid Science applied to Biology". Trans. Faraday Soc., p. 740 ; 1930.
2. Speakman, J. Soc. Dyers and Colourists, 25, 172 ; 1925.
3. Svedberg, loc. cit., p. 741.
4. Speakman, Proc. Roy. Soc, 103, B, 389 ; 1928.
5. Meyer and Mark, "Der Aufbau der Hochpolymeren Organischen Naturstoffe". Leipzig, 1930, p. 224.