The Arizona Republic reports Mesa police said Wednesday they are investigating the theft, which happened sometime during the Memorial Day weekend.
Helen Schlie, owner of Rare and Out of Print Books and Art, says the last time she saw the book was when she put it away in a fireproof box Friday night.
Schlie says it was not discovered missing until Monday afternoon when two Mormon missionaries stopped by asking to get pictures taken with the book.
Schlie says the book, which is not insured, is worth $100,000.
She says it was well-known throughout the local Mormon community that the store had an original copy.
Information from: The Arizona Republic
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