ADJOINT ORBITS OF MATRIX GROUPS OVER FINITE QUOTIENTS OF COMPACT DISCRETE VALUATION RINGS AND REPRESENTATION ZETA FUNCTIONS Michele ZordanMichele Zordan Indiana University Mathematics Journal 2018 text pdf 10.1512/iumj.2018.67.7411 10.1512/iumj.2018.67.7411 en Indiana Univ. Math. J. 67 (2018) 1683 - 1709 state-of-the-art mathematics http://iumj.org/access/