1. [1] J. Arms, R. H. Cushman, and M. J. Gotay, A universal reduction procedure for Hamiltonian group actions, The Geometry of Hamiltonian Systems (Berkeley, Calif., 1989), Math. Sci. Res. Inst. Publ., vol. 22, Springer-Verlag, New York, 1991, pp. 33–51.
2. [2] M. F. Atiyah, Convexity and commuting Hamiltonians, Bull. London Math. Soc. 14 (1982), no. 1, 1–15.
3. [3] M. F. Atiyah and R. Bott, The moment map and equivariant cohomology, Topology 23 (1984), no. 1, 1–28.
4. [4] M. Brion, Quelques propriétés des espaces homogènes sphériques, Manuscripta Math. 55 (1986), no. 2, 191–198.
5. [5] M. Brion, Sur l'image de l'application moment, Séminaire d'algèbre Paul Dubreil et Marie-Paule Malliavin (Paris, 1986), Lecture Notes in Math., vol. 1296, Springer, Berlin, 1987, pp. 177–192.