Calculation of exchange energies using algebraic perturbation theoryDOI: info:10.1103/PhysRevA.81.042508v. 8142508
Burrows, B. L., Dalgarno, Alexander, and Cohen, M. 2010. "Calculation of exchange energies using algebraic perturbation theory." Physical Review A, 81 42508. https://doi.org/10.1103/PhysRevA.81.042508.