A local global question in automorphic forms
  In this paper, we consider the $\SL(2)$ analogue of two well-known theorems about period integrals of automorphic forms on $\GL(2)$: one due to Harder-Langlands-Rapoport, and the other due to Waldspurger. 
U. K. Anandavardhanan and Dipendra Prasad
math.NT math.RT