Enid Blyton

Enid Blyton was an English writer contemporary with Agatha Christie. Following the Tenth Doctor's assertion that he didn't want "PC Plod" investigating an alien criminal, Donna Noble realised the absurdity of Agatha Christie in the middle of a murder mystery. She claimed it would be like them driving across country to find that Blyton was having tea with her character Noddy. (DW: The Unicorn and the Wasp)

Behind the scenes
The planet Mal Oreille with its boarding school is a reference to Blyton's Malory Towers series.