  We consider a class of optimal liquidation problems where the agent's
transactions create transient price impact driven by a Volterra-type propagator
along with temporary price impact. We formulate these problems as minimization
of a revenue-risk functionals, where the agent also exploits available
information on a progressively measurable price predicting signal. By using an
infinite dimensional stochastic control approach, we characterize the value
function in terms of a solution to a free-boundary $L^2$-valued backward
stochastic differential equation and an operator-valued Riccati equation. We
then derive analytic solutions to these equations which yields an explicit
expression for the optimal trading strategy. We show that our formulas can be
implemented in a straightforward and efficient way for a large class of price
impact kernels with possible singularities such as the power-law kernel.
