The Number of Gaps in Binary Pictures. - Valentin E. Brimkov; Angelo Maimone; Giorgio Nordo; Reneta P. Barneva; Reinhard Klette (ISVC, 2005)

An explicit formula for the number of tunnels in digital objects - Valentin E. Brimkov; Angelo Maimone; Giorgio Nordo (CoRR, 2005)

Counting Gaps in Binary Pictures. - Valentin E. Brimkov; Angelo Maimone; Giorgio Nordo (IWCIA, 2006)

On the Notion of Dimension in Digital Spaces. - Valentin E. Brimkov; Angelo Maimone; Giorgio Nordo (IWCIA, 2006)

Genus and Dimension of Digital Images and their Time- and Space-Efficient Computation. - Valentin E. Brimkov; Giorgio Nordo; Reneta P. Barneva; Angelo Maimone (Int. J. Shape Model., 2008)

A formula for the number of (n-2)-gap in digital n-objects - Giorgio Nordo; Angelo Maimone (CoRR, 2012)

0-Gaps on 3D Digital Curves. - Giorgio Nordo; Angelo Maimone (CoRR, 2021)