1. Introduction. A. Brauer and R. Brauer (2) and Barnes (1) (following a method of Mordell (6)) have solved the Diophantine equation x2+y2+c = xyz subject to the condition (x, y) = 1. Independently, but using the same methods, I treated (4) the equation
x2+y2+ax+ay+l = xyz,
and subsequently (5) gave a method of obtaining all integral solutions of
x2±y2+ax+by+c = xyz,
thereby generalizing (2), (1), and (4).