1. E. Merzbacher, H.W. Lewis: In Handbuch der Physik, Vol. 34, ed. by S. Flügge (Berlin-Göttingen-Heidelberg: Springer 1958) pp. 166–192
2. J.D. Garcia, R.J. Fortner, T.M. Kavanagh: Rev. Mod. Phys. 45, 111 (1973)
3. Q.C. Kessel, B. Fastrup: In Case Studies in Atomic Physics, Vol. 3, ed. By M.R.C. McDowell, E.W. Daniel (North Holland, Amsterdam 1973) pp. 137–213
4. B. Crasemann (ed.): Atomic Inner Shell Processes (Academic Press, New York 1975)
5. D.H. Madison, E. Merzbacher: Ref. 6.4, Vol. 1, pp. 1–72