Intertwined mappings Jean Ecalle, Bruno Vallet (2004) Annales de la Faculté des sciences de Toulouse : Mathématiques
Invariance of Covariance Structures Under Groups of Transformations. A. Shapiro, M.W. Browne (1991) Metrika
Invariant functions on Lie groups and Hamiltonian flows of surface group representations. W.M. Goldman (1986) Inventiones mathematicae