1. Professor, Dept. of Geomatics, Federal Univ. of Paraná, P.O. Box 19.001, 81.531-990 Curitiba, Paraná, Brazil (corresponding author).
2. Postgraduate candidate in Geoscience, Dept. of Geomatics, Federal Univ. of Paraná, P.O. Box 19.001, 81.531-990 Curitiba, Paraná, Brazil.
3. Professor, Dept. of Geomatics, Federal Univ. of Paraná, P.O. Box 19.001, 81.531-990 Curitiba, Paraná, Brazil.
4. Professor, Institute for Photogrammetry and Remote Sensing, Univ. of Karlsruhe, Kaiserstraße 12, 76128 Karlsruhe, Germany.