Extracts of letters from Euler to Johann I Bernoulli, 1739-1740
These appear as part of a French-language article by Gustav Eneström, though the extracts written by Euler and Bernoulli are in Latin.
The letters are dated 15 September 1739 (pp. 45-46), 19 January 1740 (p. 47), 20 June 1740 (pp. 47-48), and 18 October 1740 (p. 49).
Original Source Citation
Bibliotheca Mathematica, pp. 43-48.