V (G) → V (H) that preserves vertex labels. Recall that information e.g. on charges is carried by a loop if required. Since AAM tools generate their own vertex numbering rather than making use of a user-defined input numbering, they operate on different, albeit isomorphic graphs. AAMs therefore need to be compared w.r.t. isomorphism rather than identity. Two AAMs α : V (G) → V (H) and β : V (G ′ ) → V (H ′ ) are said to be equivalent if and only if there are isomorphisms φ : Clearly, the ITS graph for the restricted map is the subgraph of the ITS of the full reaction induced by the mapped vertices: