Dimension of spaces of automorphic forms

Proceedings of the AMS Symposium at Boulder, Colorado . (1965)

Author's Comments: Although the principal purpose of this paper was to review how the Selberg trace formula is combined with character formulas to calculate the dimension of various spaces of automorphic forms. it is included as a paper on representation theory because the most influential observation in the paper was the description of a possible realization of the discrete series representations on spaces of $L^2$-cohomology.