Replying to Term Paper

So, I have this term paper to do for school on an author. I'm doing my paper on A.A. Milne, the guy who wrote Winnie-the-Pooh. We have to research their works and focus mainly on that and some literary criticism of their works. We're only allowed one internet source and i have that, so does anyone know of any kinds of books or titles of books that i could get information from about his works? If anyone has any ideas, let me know.

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