198
D. Valeri
49. P. Slodowy, Simple Singularities and Simple Algebraic Groups. Lecture Notes in Mathematics,
vol. 815 (Springer, Berlin, 1980)
50. A. Zamolodchikov, Infinite extra symmetries in two-dimensional conformal quantum field
theory. Teor. Mat. Fiz. 65(3),347–359 (1985)
51. Y. Zhu, Modular invariance of characters of vertex operator algebras. J. AMS 9, 237–302
(1996)
D. Valeri
49. P. Slodowy, Simple Singularities and Simple Algebraic Groups. Lecture Notes in Mathematics,
vol. 815 (Springer, Berlin, 1980)
50. A. Zamolodchikov, Infinite extra symmetries in two-dimensional conformal quantum field
theory. Teor. Mat. Fiz. 65(3),347–359 (1985)
51. Y. Zhu, Modular invariance of characters of vertex operator algebras. J. AMS 9, 237–302
(1996)