Marc Pollefeys Luc J. Van Gool Marc Proesmans Euclidean 3D Reconstruction from Image Sequences with Variable Focal Lenghts. 31-42 1996 conf/eccv/1996-1 ECCV (1) db/conf/eccv/eccv1996-1.html#PollefeysGP96 http://dx.doi.org/10.1007/BFb0015521