  The clique-width is a measure of complexity of decomposing graphs into
certain tree-like structures. The class of graphs with bounded clique-width
contains bounded tree-width graphs. We give a polynomial time graph isomorphism
algorithm for graphs with clique-width at most three. Our work is independent
of the work by Grohe et al. \cite{grohe2015isomorphism} showing that the
isomorphism problem for graphs of bounded clique-width is polynomial time.
