1980, Austria. Original artist's painting by Prof. Otto Stefferl for the issue "11th Congress of the Intl. Association for Bridge and Structural Engineering, Vienna" showing "Old and Modern Bridges". Acrylic on card with inscription overlay and passepartout framing. Issued design. Size (netto) 254x206 mm. Some printer's notes on the reverse. UNIQUE ARTWORK. (Mi #1653) (MS) (Tax Method: Margin System) (Image)