Galactic coordinates
From Tardis Wiki, the free Doctor Who reference
Gallifrey was located in the constellation of Kasterborous, at galactic coordinates 10-0-11-00:02 from Galactic Zero Centre. (TV: Pyramids of Mars, Full Circle)
The thirteenth moon of the thirteenth planet of the Thirteenth Galaxy was located in galactic coordinates: 13:13:13:13:13:13. (COMIC: Triskaidekaphobia)
Attempting to identify a Pyrovile, the Tenth Doctor asked it for its galactic coordinates. (TV: The Fires of Pompeii)