Subdirectly Irreducible Members of Products of Lattice Varieties
George Grätzer, David Kelly · Proceedings of the American Mathematical Society · 1988
In this paper we prove: THEOREM. Let V and W be nontrivial lattice varieties. If L E V o W, then there is a subdirectly irreducible S E V o W containing L as a Sublattice. Moreover, if L is finite, S can al8o be chosen to be finite.