So's Cayley-DS conjecture for integral circulant graphs

Two graphs are cospectral when their adjacency matrices have the same eigenvalue multiset, and a circulant graph is Cayley-DS when every cospectral Cayley graph on the same group is isomorphic to it. So's conjecture. Two integral circulant graphs are isomorphic if and only if they are cospectral; equivalently, every integral circulant graph is Cayley-DS. The source presents this as an open conjecture about spectral determination of integral circulants.