Isomorphic t-(sub)norms generated by the product and Galois connections

In this paper, it is shown that, a non-decreasing bijection on the unit interval [0,1] is an isomorphism between two t-norms &1 and &2 which are both generated by the product and Galois connections if and only if its restriction to certain sub-tomonods generated by the Cayley tomonods of ([0,1),&1) and ([0,1),&2), is an isomorphism.