Hyperbolic Lie Algebras and Quasi-Regular Cusps on Hilbert Modular Surfaces. James Lepowsky; Robert V. Moody — 1979 Mathematische Annalen
Orthogonality within the families of C -, S -, and E -functions of any compact semisimple Lie group. Moody, Robert V.; Patera, Jiri — 2006 SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only]