  A finite non-abelian group $G$ is called commuting integral if the commuting
graph of $G$ is integral. In this paper, we show that a finite group is
commuting integral if its central factor is isomorphic to ${\mathbb{Z}}_p
\times {\mathbb{Z}}_p$ or $D_{2m}$, where $p$ is any prime integer and $D_{2m}$
is the dihedral group of order $2m$.

Group Theory