Pauli letter collection: letter to Niels Bohr

Pauli sends Bohr a manuscript of an unpublished work. He writes about his new interest in quantum theory and his idea to explain the anomalous Zeeman-effect through relativistic considerations. His hypothesis is that the doublet-structure of alkali spectra is alone a property of the valency-electron. He talks about the necessity for a correct formulation of the correspondence principle for atoms with more than one electron and about the necessity for a modification of the classical kinematic concept of motion.