1. E. Goldstein , Sitzungsbericht Berlin Akademie, July 1886 (unpublished), p. 25.
2. Ueber eine noch nicht untersuchte Strahlungsform an der Kathode inducirter Entladungen
3. I. G. Brown , inThe Physics and Technology of Ion Sources, edited by I. G. Brown (Wiley, New York, 1989).
4. R. Geller ,Electron Cyclotron Resonance Ion Sources and ECR Plasmas(IOP, Bristol, 1996).
5. Techniques and mechanisms applied in electron cyclotron resonance sources for highly charged ions