E. U. Condon
Rev. Mod. Phys. 14, 341 (1942) - Published 1 October, 1942
Wilfried Heller
Rev. Mod. Phys. 14, 390 (1942) - Published 1 October, 1942
S. E. Sheppard
Rev. Mod. Phys. 14, 410 (1942) - Published 1 October, 1942