Large classes of functionally complete groupoids I. J.C. Muzio, I.G. Rosenberg (1982) Aequationes mathematicae
Linear identities in graph algebras Agata Pilitowska (2009) Commentationes Mathematicae Universitatis Carolinae We find the basis of all linear identities which are true in the variety of entropic graph algebras. We apply it to describe the lattice of all subvarieties of power entropic graph algebras.
Local polynomial functions on lattices and universal algebras D. Dorninger, W. Nöbauer (1979) Colloquium Mathematicae