Cramér became interested in the rigorous mathematical formulation of probability in work of the French and Russian mathematicians such as Paul Lévy, Sergei Bernstein, and Aleksandr Khinchin in the early 1930s, but in particular the axiomatic approach of Kolmogorov .
Cramér naging interesado sa mahigpit na matematiko pagbabalangkas ng mga bagay na maaaring mangyari sa trabaho ng French at Ruso mathematicians tulad ng Paul magpataw ng buwis, Daisy Bernstein, at Aleksandr Khinchin sa unang bahagi ng 1930s, ngunit sa partikular na ang axiomatic diskarte ng Kolmogorov.