The Time Tutor by Bee Ridgway. "Ridgway is a literature professor at Bryn Mawr and the book is chock-full of witty literary references. The Time Tutor is a prequel novella to the River of No Return (also reviewed on this list). It fills in some of the back story of the secondary characters. Which, of course, meant I had to go back and read RONR again!"
