Narain, 1987, Nucl. Phys., B279, 369, 10.1016/0550-3213(87)90001-0
Gross, 1985, Nucl. Phys., B256, 253, 10.1016/0550-3213(85)90394-3
Dixon, 1986, Nucl. Phys., B274, 285, 10.1016/0550-3213(86)90287-7
Ibáñez, 1987, Phys. Lett., B187, 25, 10.1016/0370-2693(87)90066-9
Kawai, 1987, Nucl. Phys., B288, 1, 10.1016/0550-3213(87)90208-2
Lerche, 1987, Nucl. Phys., B287, 477, 10.1016/0550-3213(87)90115-5
Gepner, 1987, Phys. Lett., B199, 380, 10.1016/0370-2693(87)90938-5
Gepner, 1988, Nucl. Phys., B269, 757, 10.1016/0550-3213(88)90397-5
Green, 1989, Nucl. Phys., B324, 380
Font, 1990, Nucl. Phys., B337, 119, 10.1016/0550-3213(90)90254-B
Intriligator, 1990, Nucl. Phys., B339, 95, 10.1016/0550-3213(90)90535-L
Ginsparg, 1986, Harvard preprint HUTP-86/A090
I.B. Frenkel, J. Lepowsky and A. Meurman, Vertex operator calculus, preprint
Alvarez-Gaumé, 1987, Commun. Math. Phys., 112, 503, 10.1007/BF01218489
Verlinde, 1987, Nucl. Phys., B288, 357, 10.1016/0550-3213(87)90219-7
Vafa, 1986, Nucl. Phys., B273, 592, 10.1016/0550-3213(86)90379-2