Roger Cotes (1714) "Logometria," Philosophical Transactions of the Royal Society of London, 29 (338) : 5–45; see especially the bottom of page 10. From page 10: "Porro eadem ratio est inter 2,718281828459 &c et 1, … " (Furthermore, by the same means, the ratio is between 2.718281828459… and 1, … )
dartmouth.edu
math.dartmouth.edu
Euler, L. "De serie Lambertina Plurimisque eius insignibus proprietatibus." Acta Acad. Scient. Petropol. 2, 29–51, 1783. Reprinted in Euler, L. Opera Omnia, Series Prima, Vol. 6: Commentationes Algebraicae. Leipzig, Germany: Teubner, pp. 350–369, 1921. (facsimile)
II (Héritiers), Johann Grosse; II (Leipzig), Johann Friedrich Gleditsch; Mencke, Otto; Mencke, Johann Burkhard. Acta eruditorum: anno ... publicata (en llatí). prostant apud Joh. Grossium ... & J. F. Gleditschium, 1690.
William Shanks, Contributions to Mathematics, ... (London, England: G. Bell, 1853), page 89.