Progress of Theoretical PhysicsOn the Spur Calculations in Quantum MechanicsK. NishijimaPublished Feb 1, 1950• 1 citationPublisherAbstractK. Nishijima; On the Spur Calculations in Quantum Mechanics, Progress of Theoretical Physics, Volume 5, Issue 1, 1 February 1950, Pages 155–157, https://doi.orgDOI10.1143/ptp/5.1.155