A simulation tool for the study of satellite based navigation systems / by P.J. de Pagter, G.J. Dekker and L.J.M. JoostenStudy on navsat system simulation / by P.J. de Pagter and A.A.C. KlaasseImage data reduction with splines and segmentation with emphasis on earth observation / by P.J. de Pagter and J.J. Renes