Poisson Summation and Endoscopy for $SL(3,\mathbb R)$
  The group is interesting as the first example of split rank 2 semisimple group, all the irreducible unitary representations of which are known. We make a precise realization of the discrete series representations (in Section 2) by using the Orbit Method and Geometric Quantization, a computation of their traces (Section 3) and an exact formula for the noncommutative Poisson summation and endoscopy of for this group (in Section 4). 
Do Ngoc Diep, Do Thi Phuong Quynh
math.QA math.RT