"The Skye Boat Song"
From Tardis Wiki, the free Doctor Who reference
"The Skye Boat Song" was a tune that the Second Doctor played on his recorder near the conclusion of the London Event. It was in part a diversion to prevent Colonel Lethbridge-Stewart from overhearing his discussion with Jamie McCrimmon on the Picadilly Circus tube station platform. (TV: The Web of Fear)
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