The Lion, the Witch and the Wardrobe

From Tardis Wiki, the free Doctor Who reference

The Lion, the Witch and the Wardrobe was a book by C. S. Lewis. The Eleventh Doctor and Amy Pond inspired its creation by giving Lewis a copy of The Professor, the Queen and the Bookshop. (DWM: The Professor, the Queen and the Bookshop)

The Eighth Doctor referred to "happening upon wardrobe adventures", a central feature in the book's plot. (EDA: EarthWorld)

The Lion, the Witch and the Wardrobe