He undertook his pure mathematics studies first at the University of Berlin where he was taught by Schur, Edmund Landau Landau, Frobenius, Schottky and Planck .
Siya undertook kanyang purong matematika unang pag-aaral sa Unibersidad ng Berlin kung saan siya ay tinuturuan sa pamamagitan ng Schur, Edmund Landau Landau, Frobenius, Schottky at Planck.