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Pictures: A collection of famous celebrity authors

Ellie Simmonds has written a series of children's books, so we've taken a look at some more celebrities who have turned their hand to writing.
England football superstar Frank Lampard released his first children's book in June 2013. It was called Frankie's Magical Football.
Frank Lampard
Coemdian David Walliams has quickly become a respected name as a children's author after selling over a million copies of his books in the UK. His work has been translated into 25 other languages.
David Walliams
Comedian Ricky Gervais wrote Flanimals in 2004. The books are a showcase of made-up, useless animals and their weird behaviours.
Ricky Gervais
Daytime television host Holly Willoughby linked up with her sister to create the L'Etoile School for Stars series of children's books. The stories are set in a stage school following two friends who want stardom.
Holly Willoughby
Arsenal footballer Theo Walcott is another sporting star who has released his own series of children's stories. T.J. and the Hat-trick follows the story of a young boy at school who wants to play football.
Theo Walcott
Four-time Paralympic champion Ellie Simmonds has written a collection of books for children. The main character is based on Ellie herself and has achondroplasia, the most common form of dwarfism. Here's a peek at some other celebrities who have turned to writing.
Ellie Simmonds
Barack Obama released Of Thee I Sing: A Letter to My Daughters in 2009, before he became president of the United States. The book is a tribute to thirteen groundbreaking Americans. He wrote it to celebrate the characteristics that unite all Americans.
Barack Obama