OpenGL quad from normal

Question

Hi

Is possible to draw a quad given its normal vector, a point that is center of the quad and the size of the quad?

I know the equation of a plane with normal vector n=(a,b,c) passing through the point (x_0,y_0,z_0) is given by a(x-x_0)+b(y-y_0)+c(z-z_0)=0. (from here)

But how to find the coordinate of the four vertex of the quad?

Thanks