Reference Label	Details
Ivanic 1997	J. Ivanic, G. J. Atchity, and K. Ruedenberg, J. Chem. Phys. 107, 4307-4317 (1997) Violation of the Weak Noncrossing Rule between Totally Symmetric Closed-Shell States in the Valence-Isoelectronic Series O3, S3, SO2, and S2O