1. Anderson, E. C., Arnold, J. R. and Libby, W. F.Science, 1949,109, 227.
2. Arnold, J. R., Honda, M. and Lal, D.Journal of Geophysical Research, 1961,66, 3519.
3. Bien, G. S., Suess, H. E. and Rakestraw, N. W.Tellus, 1960,12, 436.
4. Craig, H... Ibid., 1957,9, 1.
5. de Vries, H. .. “Measurement and use of natural radiocarbon” inResearch in Geochemistry, Edited by P. H. Abelson, John Wiley and Sons, Inc. (Lond.), 1959.