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Valence bond methods

T Dunning, L Xu, D Cooper, P Karadakov, Spin-Coupled Generalized Valence Bond Theory: New Perspectives on the Electronic Structure of Molecules and Chemical Bonds, JPCA 125, 2021 (2021)

W Wu, P Su, S Shaik, P Hiberty, Classical Valence Bond Approach by Modern Methods, CR 111, 7557 (2011)

S Shaik, P C Hiberty, A chemist's guide to valence bond theory (Wiley, 2008)

G A Gallup, Valence Bond Methods: Theory and Applications (CUP, 2003)