[en] In a previous paper with G. Gibbons (1987) we derived a list of three dimensional symmetric space σ-models obtained by dimensional reduction of a class of four dimensional gravity theories with abelian gauge fields and scalars. Here we give a detailed analysis of their group theoretical structure leading to an abstract parametrization in terms of ''triangular'' group elements. This allows for a uniform treatment of all these models. As an interesting application we give a simple derivation of a ''quadratic mass formula'' for strictly stationary black holes. (orig.)