Emily Dickinson
Emily Dickinson was a poet favoured by Suzie Costello. Her poem "The Chariot" was used by Suzie, through Max Tresilian, to lock down the Torchwood Hub.
To unlock it, Jack Harkness had Detective Kathy Swanson buy Emily Dickinson: The Complete Poems, and was prepared to go through every single poem in the book. After they tried at least "Success is Counted Sweetest" and "My Life Closed Twice Before Its Close", Toshiko Sato realised that the code wasn't another poem, but a series of numbers — the ISBN. (TV: They Keep Killing Suzie)
Meeting a young girl named Emily, the Twelfth Doctor acknowledged Dickinson among a list of famous women who shared her name. (COMIC: Harvest of the Daleks)