Saurabh Garg Jayanthi Sivaswamy Siva Chandra Unsupervised Curvature-Based Retinal Vessel Segmentation. 344-347 2007 ISBI http://dx.doi.org/10.1109/ISBI.2007.356859 conf/isbi/2007 db/conf/isbi/isbi2007.html#GargSC07