Wong Li Yun U. Rajendra Acharya Y. V. Venkatesh Caroline Chee Lim Choo Min E. Y. K. Ng Identification of different stages of diabetic retinopathy using retinal optical images. 106-121 2008 178 Inf. Sci. 1 http://dx.doi.org/10.1016/j.ins.2007.07.020 db/journals/isci/isci178.html#YunAVCMN08