 After completing his master's degree at Leiden University from 1918–1922 he studied at the University of Copenhagen with Harald Bohr and the University of Oxford with G. H. Hardy.In 1924 he received his Ph.D. in Leiden under supervision of J. C. Kluyver.From 1926 to 1928 he studied at the universities of Göttingen and Hamburg, and he was assistant at the University of Münster from 1928-1930.