Reference Label	Details
Huber 1979	K. P. Huber and G. Herzberg, "Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules", Van Nostrand Reinhold: New York 1979
note unc	The quoted uncertainty appeared to correspond to one std dev. and was multiplied by 2 to come closer to the desired 95% confidence limit
Miller 1975	T. A. Miller, R. S. Freund, B. R. Zegarski, R. Jost, M. Lombardi, and J. Derouard, J. Chem. Phys. 63, 4042-4046 (1975) Observation of Singlet-Triplet Anticrossings in 4He2