1. E.K. Hyde, M.H. Studier, W.H. Manning – Priv. Comm., quoted by [1964Hy02] unpublished (1948)
2. Half-Life of Plutonium-240 by Determination of Its Uranium-236 Daughter
3. D.A. Orth, K. Street, Jr. – Priv. Comm., quoted by [1958St50] unpublished (1951)
4. J.C. Wallmann – Thesis, Univ. California (1951); UCRL-1255 (1951)