| Reference Label | Details |
|---|---|
| Moore 1970 | C. E. Moore, "Ionization Potentials and Ionization Limits Derived from Analyses of Optical Spectra", NSRDS-NBS 34, National Bureau of Standards: Washington, DC 1970 |
| McConkey 1968 | J. W. McConkey and J. A. Kernahan, Phys. Lett. A 27, 82-83 (1968) The Ionization Limits of N I |