1. Bird K, Sherwin M (2006) American prometheus. Alfred A. Knopf, New York
2. Bohr N (1961) A letter to Mrs. Sugiura, dated February 8, 1961. In: Niels Bohr Archive, Niels Bohr scientific correspondence, 1903–1962, Folder 335, Item 4:Bohr to Mrs. Sugiura, 1927-06-01
3. Born M (1978) My life. Taylor and Francis, London
4. Dirac PAM (1925) The fundamental equations of quantum mechanics. Proc R Soc A 109:642–635
5. Dirac PAM (1926) Quantum mechanics and a preliminary investigation of the hydrogen atom. Proc R Soc A 110:561–579