Preservation under Extensions on Well-Behaved Finite Structures.

Albert Atserias Anuj Dawar Martin Grohe Preservation under Extensions on Well-Behaved Finite Structures. 1364-1381 2008 38 SIAM J. Comput. 4 http://dx.doi.org/10.1137/060658709 db/journals/siamcomp/siamcomp38.html#AtseriasDG08