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- Morris, Henry, 1855-19293
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- Morton, W. T. G. (William Thomas Green), 1819-18683
- Mott, Valentine, 1785-18653
- Nelson, Norton A., author3
- New York (N.Y.). Board of Health.3
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- Niemeyer, Felix von, 1820-18713
- Nightingale, Florence, 1820-19103
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