The Winter's Tale was a play by William Shakespeare. The Eleventh Doctor interrupted a rendition of the play, thinking that the statue of the dead Hermione was a Weeping Angel. (PROSE: The Winter's Tale)
When Richard Maynarde and Lady Peinforte approach the tomb containing Nemesis, they hear a noise which he claims sounds like a bear. Lady Peinforte just replies "Come, the bear will not pursue us; such things only happen in the theater", referring to the infamous stage direction in the play, "Exit, pursued by a bear". (TV: Silver Nemesis)