I have had a lot of fun drawing some regions and surfaces using the Draw package. Thank you Mario for the great work. I encountered a small problem in trying to plot the region bounded by x=y-y^2 and the y-axis. Namely, implicit(x=y-y^2,x,0,1/4,y,0,1) results in a Lisp error, while replacing 1/4 by 0.25 works fine. hth, Milan --