Automorphic period and the central value of Rankin--Selberg L-function
  We prove a refinement of the global Gan-Gross-Prasad conjecture proposed by Ichino-Ikeda and N. Harris for unitary groups under some local conditions. We need to assume some expected properties of L-packets and some part of the local Gan-Gross-Prasad conjecture. 
Wei Zhang
math.NT math.RT