Reference Label	Details
est unc	estimated uncertainty
Chung 1979	K. T. Chung, Phys. Rev. A 20, 724 (1979) Triply Excited Bound State of He- and the Isoelectronic Sequence
Tech 1971	J. L. Tech and J. F. Ward, Phys. Rev. Lett. 27, 367 (1971) Accurate Wavelength Measurement of the 1s2p 3P° - 2p2 3P Transition in 4He