Sir Arthur Conan Doyle was a Scottish writer who wrote the famous Sherlock Holmes books and short stories. (TNG: "Lonely Among Us")
Captain Spock once implied that he was a descendent of Doyle's, presumably via his human mother Amanda Grayson. (Star Trek VI: The Undiscovered Country)
Data was very much interested in the works of Arthur Conan Doyle and it was Captain Picard who introduced him to the author. (TNG: "Data's Day")
Background information
Star Trek VI: The Undiscovered Country director and screenplay writer Nicholas Meyer had previously written the screenplay for The Seven-Per-Cent Solution, based on his novel. The film and book feature Sherlock Holmes, Arthur Conan Doyle's creation. This may be the reason that Spock implies that he is a descendent of Doyle's.