Abstract. It has been recently shown  that the lattice effect algebras can be treated as a subvariety of the variety of so-called basic algebras. The main goal of this paper is to describe the variety of basic algebras generated by the horizontal sum of two 3-element MV-chains. It is shown that this variety is modulo the variety of distributive lattice effect algebras characterized by a unique simple identity.
AMS Subject Classification
(1991): 08A30, 08B10
Lattice effect algebra,
Received April 26, 2007, and in revised form November 22, 2007. (Registered under 6002/2009.)