Referee's Report by [John Douglas] Cockcroft on a paper 'The influence of magnetic fields on persistent currents in superconductors' by K C Mann, H [Grayson] Smith, and J O Wilhelm Paper reference code: A.71 Sectional committee: Physics References a measurement by de Haas, and explains that the authors' argument contradicts [A D] Misener's results (Proc. Roy. Soc. [Proceedings of the Royal Society], 1938). Critiques the paper's conclusions. [Not published in RS journals but published in the Physical Review, v. 54, 758, Nov. 1938]. Received 25 May 1938 24 May 1938