‎"KRAMERS, H.A. - THE DOCTORAL THESIS.‎
‎Intensities of Spectral Lines. On the Application of the Quantum Theory to the Problem of the relaive Intensities of the Components of the Fine Structure and of the Stark Effect of the Lines of the Hydrogen Spectrum. With four Plates.‎

‎København, Høst & Søn, 1919. 4to. Orig.printed wrappers. (Offprint issue from ""D. Kgl. Danske Videnskabernes Selskab. Skr. Nat. Vid og Math. Afd. 8. Række, III.3.). Pp. 285-384,(2) a. 4 plates. Lower margin of frontwrapper faded.‎

Reference : 42955

‎Fist printing of Kramer's doctoral thesis in which he calculated the relative intensities of the fine-structure components on the Basis of Bohr's Correspondence Principle and obtained results which generally agreed with Paschen's measurements.Bohr had concluded ""that polarizations and intensities should, in the limit of high quantum numbers, be given by the Fourier components of the quantized motion and that even at low quantum numbers the Fourier components in the initial and final states should give an indication of the intensities to be expected. In his doctoral thesis at Leiden in 1919 (published by the Royal Danish Academy of Sciences) - the paper offered - Kramers developed the mathematical formalism required to apply these ideas"" he also carried out detailed calculations for the case of a hydrogen atom in an external electric field. This led to a satisfactoery interpretation of the intensities of Stark components.""(H.B.G. Casimir in DSB VII, p. 491).‎