1. Balbes R., Dwinger P. (1974). Distributive Lattices. University of Missouri Press, Columbia
2. Bignall, R. J., and M. Spinks, ‘On binary discriminator varieties, I: Implicative BCS-algebras’, International Journal of Algebra and Computation, To appear.
3. Blok,W. J., and D. Pigozzi, ‘Abstract Algebraic Logic and the Deduction Theorem’, Manuscript, 2001.
4. Blok W.J., Raftery J.G. (1995). ‘On the quasivariety of BCK-algebras and its subvarieties’. Algebra Universalis 33, 68–90
5. Blok W.J., Raftery J.G. (1997). ‘Varieties of commutative residuated integral pomonoids and their residuation subreducts’. Journal of Algebra 190, 280– 328