Here's an interesting article about Joy Davidman, the American woman C.S.
Lewis married at age 56.
Lyle Dorsett's biography is titled, And God Came In: The Extraordinary Story of Joy Davidman. Don King edited the valuable, Out of My Bone: The Letters of Joy Davidman.
See also Davidman's book dedicated to C.S. Lewis, Smoke on the Mountain: An Interpretation of the Ten Commandments.
A list of C.S. Lewis's publications may be found here.