1. H. Kamerling Onnes, Further experiments with liquid helium. C. On the change of electric resistance of pure metals at very low temperatures etc. IV. The resistance of pure mercury at helium temperatures, Leiden Comm. 120b (28 April 1911); V. The disappearance of the resistance of mercury ibid., 122b (27 May 1911 ).
2. H. K. Onnes, Sur les resistances électriques, Solvay Congress Nov. 1911, Leiden Comm. Supply No. 29.
3. H. K. Onnes, VII. The potential difference necessary for the electric current through mercury below 4°19 K, Leiden Comm. 133a (22 Feb. 1913); V III. The sudden disappearance of the ordinary resistance of tin and the super-conductive state of lead, ibid., 133d (31 May 1913 ).
4. H. K. Onnes and W. Tuyn, X. Measurements concerning the electrical resistance of thallium in the temperature field of liquid helium, Leiden Comm. 160a (28 Oct. 1922 ).
5. W. Tuyn and H. K. Onnes, XII.Measurements concerning the electrical resistance of indium…., Leiden Comm. 167a (30 June 1923 ).