?url_ver=Z39.88-2004&rft_id=10.1109%2FICIAS.2018.8540587&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=P.&rft.aulast=Porwal&rft.au=Porwal%2C+P.&rft.isbn=9781538672693&rft.title=Automatic+Segmentation+of+Optic+Disc+by+Gradient+Minimization+Based+Approach&rft.date=2018&rft.genre=proceeding