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G. F. Koster and H. Statz, J. Appl. Phys. 32, 2054 (1961).

H. Statz, C. L. Tang, and G. F. Koster, J. Appl. Phys. 34, 2625 (1963).

W. L. Faust and R. A. McFarlane, J. Appl. Phys. 35, 2010 (1964).

For example, R. H. Garstang, Mon. Not. Roy. Astron. Soc. 114, 118 (1954).

E. U. Condon and G. H. Shortley, Theory of Atomic Spectra (Cambridge University Press, New York, 1952), pp. 298, 197, 268, 299.

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Ref. 6, p. 385.

Ref. 6, pp. 298, 299, 316.

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D. R. Bates and A. Damgaard, Phil. Trans. Roy. Soc. (London) A242, 101 (1949).

We have elected to use the Paschen notation for the energy levels, because we believe this makes comparison with other work easier. The pair-coupling notation may be found in Ref. 7.

In one or two cases there was some uncertainty as to which *LS*-coupling level should be correlated with a given observed level. We adopted the guide that the *LS*-coupling level was the one which referred to the same diagonal-element position in the initial *LS*-coupling energy matrix that the calculated energy had in the final diagonal energy matrix.

Ref. 6, p. 311.

Formula (4) in Ref. 2 is correct as far as it goes, but it must be summed over the polarization index *q*, and hence multiplied by a factor 3, to give absolute line strengths. The same factor 3 must be applied to formulas (2.1) and (2.1a) of Ref. 3. Table IV of Ref. 3 is erroneous, and all entries in it must be multiplied by 4π/3, as must formula (2.2) of the same reference. See footnote 19 of Ref. 4 for further details.

H. N. Olsen, J. Quant. Spectry. Radiative Transfer 3, 59 (1963).

L. R. Doherty, thesis, University of Michigan (1961).

A. P. Thorne and J. E. Chamberlain, Proc. Phys. Soc. (London) 82, 133 (1963).

L. P. Razumovskaya, Opt. i Spektroskopiya 14, 189 (1963). [English transl.: Opt. Spectry. 14, 98 (1963).]

W. E. Gericke, Z. Astrophys. 53, 68 (1961).

H. W. Drawin, Z. Physik 146, 295 (1956).