Flora Rheta Schreiber (April 24, 1918 – November 3, 1988), an American journalist, was the author of the 1973 bestseller Sybil, the story of a woman (identified years later as Shirley Ardell Mason) who had a dissociative identity disorder and allegedly had 16 different personalities. As Mason had insisted on protection of her privacy, Schreiber gave her the cover identity of Sybil Isabel Dorsett.
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