Linear Quadratic Stochastic Two-Person Zero-Sum Differential Games in an   Infinite Horizon
  This paper is concerned with a linear quadratic stochastic two-person zero-sum differential game with constant coefficients in an infinite time horizon. Open-loop and closed-loop saddle points are introduced. The existence of closed-loop saddle points is characterized by the solvability of an algebraic Riccati equation with a certain stabilizing condition. A crucial result makes our approach work is the unique solvability of a class of linear backward stochastic differential equations in an infinite horizon. 
Jingrui Sun, Jiongmin Yong, and Shuguang Zhang
math.OC