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  1. T. S. Blyth, Jie Fang & Lei-bo Wang (forthcoming). De Morgan Algebras with a Quasi-Stone Operator. Studia Logica:1-16.
    We investigate the class of those algebras (L; º, *) in which (L; º) is a de Morgan algebra, (L; *) is a quasi-Stone algebra, and the operations ${x \mapsto x^{\circ}}$ and ${x \mapsto x^{*}}$ are linked by the identity x**º = x*º*. We show that such an algebra is subdirectly irreducible if and only if its congruence lattice is either a 2-element chain or a 3-element chain. In particular, there are precisely eight non-isomorphic subdirectly irreducible Stone de Morgan algebras.
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  2. T. S. Blyth, Jie Fang & Leibo Wang (forthcoming). On Ideals and Congruences of Distributive Demi-P-Algebras. Studia Logica:1-16.
    We identify the \({{}^\star}\) -ideals of a distributive demi-pseudocomplemented algebra L as the kernels of the boolean congruences on L, and show that they form a complete Heyting algebra which is isomorphic to the interval \({[G,\iota]}\) of the congruence lattice of L where G is the Glivenko congruence. We also show that the notions of maximal \({{}^\star}\) -ideal, prime \({{}^\star}\) -ideal, and falsity ideal coincide.
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  3. Jie Fang, Lei-Bo Wang & Ting Yang (2014). The Lattice of Kernel Ideals of a Balanced Pseudocomplemented Ockham Algebra. Studia Logica 102 (1):29-39.
    In this note we shall show that if L is a balanced pseudocomplemented Ockham algebra then the set ${\fancyscript{I}_{k}(L)}$ of kernel ideals of L is a Heyting lattice that is isomorphic to the lattice of congruences on B(L) where ${B(L) = \{x^* | x \in L\}}$ . In particular, we show that ${\fancyscript{I}_{k}(L)}$ is boolean if and only if B(L) is finite, if and only if every kernel ideal of L is principal.
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  4. Jie Fang (2008). Ockham Algebras with Balanced Double Pseudocomplementation. Studia Logica 90 (2):189 - 209.
    In this paper, we introduce a variety bdO of Ockham algebras with balanced double pseudocomplementation, consisting of those algebras of type where is an Ockham algebra, is a double p -algebra, and the operations and are linked by the identities [ f ( x )]* = [ f ( x )] + = f 2 ( x ), f ( x *) = x ** and f ( x + ) = x ++ . We give a description of the (...)
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  5. T. S. Blyth & Jie Fang (2007). Congruence Coherent Symmetric Extended de Morgan Algebras. Studia Logica 87 (1):51 - 63.
    An algebra A is said to be congruence coherent if every subalgebra of A that contains a class of some congruence on A is a union of -classes. This property has been investigated in several varieties of lattice-based algebras. These include, for example, de Morgan algebras, p-algebras, double p-algebras, and double MS-algebras. Here we determine precisely when the property holds in the class of symmetric extended de Morgan algebras.
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