M. Fowler and R. E. Prange
Physics Physique Fizika 1, 315 (1965) - Published 1 July, 1965
D. H. Douglass, Jr.
Physics Physique Fizika 1, 329 (1965) - Published 1 July, 1965
W. R. Abel, A. C. Anderson, W. C. Black, and J. C. Wheatley
Physics Physique Fizika 1, 337 (1965) - Published 1 July, 1965