Paris: Galerie Alexandre Iolas, 1974. hardcover. Exhibition catalogue, printed on thick cardstock with alphabet tabs. Illustrated throughout with Nellens' unusual mechanical drawings, many in color. Short 4to, pictorial boards with cloth spine (a beautifully designed but poorly constructed book -- most copies, this one included, have detached pages because they were glued, not sewn). Paris: Galerie Alexandre Iolas, . A very scarce catalogue. in very good condition. very good.