(Berlin, Haude & Spener, 1770). 4to. No wrappers, as issued in "Memoires de l'Academie Royale des Sciences et Belles-Lettres", tome XXIV, pp. 181-250. Clean and fine.
First edition. An importent paper in the Theory of Numbers. The year before Lagrange gave a complete solution to the problem of giving all integral solutions of a special general equation (Sur la Solution des Problemes Indéterminés du Second Degré). In this paper he sets up a simpler proof of the same problem. - Cajori calls Lagrange "One of the greatest mathematicians of all times". - Poggendorff I:1344.
Order-nr.: 35218