Wilfried Linder, born in 1959, studied mathematics and geography at the University of Hannover (1979-85). Thereafter, he was employed as a scientific assistant at the Universities of OsnabrA1/4ck/Vechta, Hannover and DA1/4sseldorf. In 1990 he received his Ph.D in geography, followed in 1993 by one in geodesy. He is now a member of the Institute of Geography at the University of DA1/4sseldorf, where he is responsible for the fields of photogrammetry, remote sensing, digital cartography and geo information systems (GIS).