Elena Franchini Serena Morigi Fiorella Sgallari Composed Segmentation of Tubular Structures by an Anisotropic PDE Model. 75-86 2009 SSVM http://dx.doi.org/10.1007/978-3-642-02256-2_7 conf/scalespace/2009 db/conf/scalespace/ssvm2009.html#FranchiniMS09