Mrs. Lettie.B. Cowman (1870-1960) and her husband, Charles E. Cowman (-1923), were missionaries in Japan and China from 1901 to 1917, during which period they helped found the Oriental Missionary Society. After her husband‘s death Mrs. Cowman wrote a nine books. The ones I know of are:
Mrs. Cowman inspired several nationwide Scripture distribution campaigns and wrote seven more books. Finally, on Easter Sunday in 1960, at the age of ninety,
The importance of Mrs Cowman is her frequent quoting of J.R.M.