The Famous Five

 The Famous Five  was a series of mystery books written by Enid Blyton. One of the members of the Famous Five was a dog named Timmy. (AUDIO: Changing of the Guard)

According to the Tenth Doctor, The Troubleseekers books were rip-offs of this series and The Secret Seven. (PROSE: The Mystery of the Haunted Cottage)

In 1965, Templeton derisively told Ian Gilmore he wasn't Timmy of the Secret Seven. Gilmore deadpanned that he was confusing it with the Famous Five. (AUDIO: Changing of the Guard)

In an alternate timeline created by Lenny Kruger in which the Common Men rose to prominence in place of the Beatles, John Lennon was a member of a group called the Famous Five, which was a joke name because there were only four of them: him, two Petes and Chas. (AUDIO: 1963: Fanfare for the Common Men)

Behind the scenes
Gary Russell played Dick Kirren in the of The Famous Five. Other actors who appeared in the series were Patrick Troughton, Leslie Schofield, Cyril Luckham, Michael Sheard, Geoffrey Bayldon and Leon Eagles.