| 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 |
| est unc | estimated uncertainty |
| Minnhagen 1969 | L. Minnhagen, private communication to C. E. Moore Note: apud Moore NSRDS-NBS 34 |