  This paper is concerned with a three-level stochastic linear-quadratic
Stackelberg differential game with asymmetric information, in which three
players participate credited as Player 1, Player 2 and Player 3. Player 3 acts
as the leader of Player 2 and Player 1, Player 2 acts as the leader of Player 1
and Player 1 acts as the follower. The asymmetric information considered is:
the information available to Player 1 is based on the sub-$\sigma$-algebra of
the information available to Player 2, and the information available to Player
2 is based on the sub-$\sigma$-algebra of the information available to Player
3. By maximum principle of forward-backward stochastic differential equations
and optimal filtering, feedback Stackelberg equilibrium of the game is given
with the help of a new system consisting of three Riccati equations.
