Free Algebras in Varieties of Glivenko MTL-algebras Satisfying the Equation 2(x2) = (2x)2.

Roberto Cignoli Antoni Torrens Free Algebras in Varieties of Glivenko MTL-algebras Satisfying the Equation 2(x2) = (2x)2. 157-181 2006 83 Studia Logica 1-3 http://dx.doi.org/10.1007/s11225-006-8302-8 db/journals/sLogica/sLogica83.html#CignoliT06