Dr Seuss
From Tardis Wiki, the free Doctor Who reference
Dr Seuss wrote the works contained in A Classic Case of Dr Seuss, which a young Grant had on a shelf in his bedroom. (TV: The Return of Doctor Mysterio)
According to the Sixth Doctor there was a planet devoted to the works of Doctor Seuss. He had been tempted to go there in the past, especially to try the green eggs and ham. (AUDIO: Trouble in Paradise)
Behind the scenes
The Sixth Doctor wanting try "green eggs and ham" is in reference to Seuss's book of the same name.
Seuss also created the Grinch, the titular character of his book How the Grinch Stole Christmas.