\input zb-basic \input zb-ioport \iteman{io-port 70477376} \itemau{Karron, Daniel B.; Cox, James} \itemti{Extracting 3D objects from volume data using digital Morse theory} \itemso{CVRMed, 481-486 (1995).} \itemcc{} \itemut{} \itemli{doi:10.1007/BFb0034990} \end