We formulate the notion of an isomorphism of GKM graphs. We then show that two GKM graphs have isomorphic graph equivariant cohomology algebras if and only if the graphs are isomorphic.
"Graph equivariant cohomological rigidity for GKM graphs." Proc. Japan Acad. Ser. A Math. Sci. 95 (10) 107 - 110, December 2019. https://doi.org/10.3792/pjaa.95.107