Referee's report by Douglas Rayner Hartree, on a paper 'The replusive forces between isotopic molecules' by Ronald Percy Bell Sectional Committee: Physics Recommended for publication in the 'Proceedings of the Royal Society of London'. Suggests areas requiring clarification, and rewrites of the formulae. Suggests submitting the paper to another referee with more familiarity with recent work on the subject, such as John Edward Lennard-Jones. [Published in the 'Proceedings of the Royal Society of London'] Endorsed on verso as received 28 August 1939. [August 1939]