F. Bernardi, A. Bottoni, M. J. Field, M. F. Guest, I. H. Hillier, M. A. Robb, and A. Venturini, “MC-SCF Study of the Diels-Alder Reaction Between Ethylene and Butadiene,” J. Am. Chem. Soc., 110 (1988) 3050-55. DOI: 10.1021/ja00218a009
F. Bernardi, A. Bottoni, M. J. Field, M. F. Guest, I. H. Hillier, M. A. Robb, and A. Venturini, “MC-SCF Study of the Diels-Alder Reaction Between Ethylene and Butadiene,” J. Am. Chem. Soc., 110 (1988) 3050-55. DOI: 10.1021/ja00218a009
