Lettie Burd Cowman (March 3, 1870 – April 17, 1960), also known as L.B. Cowman, was an American writer and author of the devotional books Streams in the Desert and Springs in the Valley. Cowman published her books under the author name Mrs. Charles E. Cowman. She was also one of the cofounders of The Oriental Missionary Society (later known as OMS International, and eventually One Mission Society).
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