Citation: E. Ley-koo et al., Relativistic electronic structure calculations with positive-energy and negative-energy orbitals, J MOL ST-TH, 527, 2000, pp. 11-25
Citation: Cf. Bunge et al., Variational incorporation of negative-energy orbitals in relativistic electronic structure calculations, INT J QUANT, 80(3), 2000, pp. 461-470