Malet, Antoni «James Gregorie on tangents and the "Taylor" rule for series expansions». Archive for History of Exact Sciences. Springer-Verlag, 46, 2, 1993, pàg. 97–137. DOI: 10.1007/BF00375656. «Gregorie's thought, on the other hand, belongs to a conceptual framework strongly geometrical in character. (page 137)»
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See, e.g., Marlow Anderson, Victor J. Katz, Robin J. Wilson, Sherlock Holmes in Babylon and Other Tales of Mathematical History, Mathematical Association of America, 2004, p. 114.