(46.3): P. Schuurmans, Thesis, Amsterdam, 1946.

(57.4): M.G. Morozova and G.P. Startsev, Optika Spektrosk., S.S.S.R., 1960, 2, 282-4 (trad.: Optics Spectr., U.S.S.R., U.S.A., 1957, 2, 382-4).

(71.2): L. Brewer, J. opt. Soc. Am., 1971, 61, 1666-82.

(78.8): L.A. Korostyleva and Y. P. Dontsov, Tables of Spectral lines of neutral and ionized atoms of uranium, Acad. Sci. S.S.S.R., Moscow, 1978, 221 pp.

(80.1): J.O. Berg, T.E. Christensen, P.W. Kidd, G.R. Neil and J.G. Conway, J. opt. Soc. Am., 1980, 70, 716-9.

(82.1): R.T. Schneider and T.E. Roxey, Appl. Opt., U.S.A., 1982, 21, 4204-6.

(82.3): H.M. Crosswhite, Gmelin Handbook of inorganic chemistry, 8th edition, Uranium Suppl., 1982, 1-68, Springer-Verlag.

(84.2): J.G. Conway and E.F. Worden, J. opt. Soc. Am. B, 1984, 1, 78894.

(84.4): B.A. Palmer and R. Engleman Jr., J. opt. Soc. Am. B, 1984, 1, 609-25.

(84.7): J. Blaise, J.F. Wyart, B.A. Palmer and R. Engleman Jr., 16th Conf. Europ. Group Atomic Spectrosc., London, U.K., 1984, Europhys. Conf. Abstr., 8H, A4-14.

(87.7): J. Blaise, J.F. Wyart, B.A. Palmer, R. Engleman Jr. and F. Launay, 19th Conf. Europ. Group Atomic Srectrosc., Dublin, Eire, Europhys. Conf. Abstr., 1987, 11E, Comm. A3-08.

(unp.14): J.G. Conway and C.H.H. Van Deurzen.

(unp.18): R. Engleman Jr.