1963 With S. Hagstrom. The nature of the two-electron chemical bond. III. Natural orbitals for H2. Rev. Mod. Phys. 35:624-629.
1964 With F. Prosser. The nature of the two-electron chemical bond. IV. Natural orbitals for He2++. J. Chem. Phys. 40:233-235.
The nature of the two-electron chemical bond. V. Electron pairing and H3+. J. Am. Chem. Soc. 86:1469-1474.
With B. G. Anex. The nature of the two-electron chemical bond. VI. Natural orbital analysis for HeH+. In Molecular Orbitals in Chemistry, Physics and Biology, eds. P.-O. Löwdin and B. Pullman, pp. 227-239. New York: Academic Press.
1965 With G. P. Barnett and J. Linderberg. Approximate natural orbitals for four-electron systems. J. Chem. Phys. 43:580-588.
1966 With F. Prosser. Quantum chemistry. Annu. Rev. Phys. Chem. 17:37-58.
1967 With G. P. Barnett. Reduced density matrix theory: The two-matrix of four electron systems. Phys. Rev. 153:61-73.
1968 With R. E. Christoffersen. Nature of the two electron chemical bond. VII. J. Chem. Phys. 48:1790-1797.
1970 The two-electron chemical bond. In Physical Chemistry, An Advanced Treatise, vol. V, Valency, eds. H. Eyring, D. Henderson, and W. Jost, pp. 125-171. New York: Academic Press.
1973 With D. H. Busch and R. T. Conley. Chemistry. Boston: Allyn and Bacon.