Bud, Robert; Warner, Deborah Jean; Chaplin, Simon; Johnston, Stephen; Peterson, Betsy Bahr (1998). Instruments of Science: An Historical Encyclopedia. Science Museum, London, and National Museum of American History, Smithsonian Institution. ISBN9780815315612. Retrieved 2009-10-11.
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Dick, William Brisbane (1975). "Degrees of Baum'e". Dick's Encyclopedia of Practical Receipts and Processes. New York: Dick and Fitzgerald, Publishers. ISBN9780308101579.