When his war service had ended in 1946, Krull took up again his post at the University of Bonn and he would remain there for the rest of his life.
Kapag ang kanyang mga digmaan serbisyo ay natapos sa 1946, Krull took up muli ang kanyang mga post sa Unibersidad ng Bonn at siya ay manatili doon para sa natitirang bahagi ng kanyang buhay.