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Haining, Peter. Agatha Christie: Murder in Four Acts. Great Britain: Virgin Books, 1990.
Keating, H.R.F. Agatha Christie: First Lady of Crime. New York: Holt, Rinehart and Winston, 1977.
Osborne, Charles. The Life and Crimes of Agatha Christie. London: HarperCollins, 1982.
Wagoner, Mary S. Agatha Christie. Boston: G.K. Hall & Co., 1986.
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