Who is the famous british author that is said to be the best selling author in the history of the childrens litreture?

It appears on books sales Only 2 authors have surpass her sales up to her death

Tale of 2 cities by Charles Dickens with 200 million and Lord of the rings by J. R. R. Tolkien

in 1968 at the time of her death Enid Blyton had sold 111 million books and these have continued to see in had and electronic copy ever since