ショールズ・アンド・グリデン・タイプライター
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Thompson, Holland (1921). The Age of Invention: A Chronicle of Mechanical Conquest. New Haven: Yale University Press. https://archive.org/details/ageinventionach01thomgoog.
Weller, Charles Edward (1918). The Early History of the Typewriter. New York: Henry Holt and Company. https://archive.org/details/earlyhistorytyp00wellgoog.
“The Type Writer”. Scientific American 6 (27): 79. (August 1872). http://kanji.zinbun.kyoto-u.ac.jp/~yasuoka/QWERTY/1872-08-10.djvu.