B. A. Hess, “Relativistic electronic-structure calculations employing a 2-component no-pair formalism with external-field projection operators,” Phys. Rev. A, 33 (1986) 3742-48. DOI: 10.1103/PhysRevA.33.3742
B. A. Hess, “Relativistic electronic-structure calculations employing a 2-component no-pair formalism with external-field projection operators,” Phys. Rev. A, 33 (1986) 3742-48. DOI: 10.1103/PhysRevA.33.3742
