She died Thursday, HarperCollins said in a statement.
In its first year out, the book sold 500,000 copies and won the Pulitzer.
She was working a nonfiction story about a murderous Alabama preacher.

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Soon Lee began swearing that shed changed her mind: Shed never publish another book.
Was this purely a cash grab by Lees lawyer and caretaker, Tonja B. Carter?
And finally: What would the bookwhich portrays Atticus Finch as a card-carrying racist, do to Mockingbirds legacy?
Lee never addressed theWatchmancontroversy in an interview.
Thats not surprising since she spoke only rarely to the press, granting her last interview in 1964.
I will always cherish the time I spent with her.
She was quoting Thomas More and setting me straight on Tudor history.
We have lost a great writer, a great friend and a beacon of integrity.