On the Solution of the Differential Equation (∂2∂x∂y+ax∂∂x+by∂∂y+cxy+∂∂t)P=0

The following solution is obtained: P(x,y,t)=e−γxy−δP0(e−αx,e−βy,e), where P0(x, y, t) is the solution when the constants a, b, and c are zero, and where the time functions α, …, e are given explicitly.