Bulletin of the Australian Mathematical Society: Volume 13 -

Splitting torsion theories over commutative rings
John D. Fuelberth, James Kuzmanovich, Thomas S. Shores
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17 April 2009, pp. 457-464
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The purpose of this paper is to completely characterize splitting torsion theories over commutative rings. In particular, if (T, F) is a torsion theory for which T(R) = 0, then (T, F) is a splitting theory if and only if T contains only a finite number of nonisomorphic simple modules and every module in T is semisimple injective. In addition, an ideal theoretic characterization of splitting torsion theories is given, of which one consequence is that splitting torsion theories are TTF; furthermore, if R is also noetherian, then such torsion theories are centrally splitting. The known theorems concerning the splitting of the Goldie and simple torsion theories (for commutative rings) are derived from our theorem.

Multifunctions of Souslin type: Corrigendum
S.J. Leese
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17 April 2009, pp. 159-160
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In [1], Theorem 6, a sufficient condition is given for a multifunction to be “of Souslin type”. However, the proof contains an error; we are required to prove that the multifunction Ω: S→ P×NN defined by
has values which are closed subsets of P×NN (the notation is explained in [1]). The “proof” of this fact given in [1] is manifestly incorrect as it appears to assume that NN has the discrete topology.

Nonstandard topological extensions: Addendum
Robert A. Herrmann
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17 April 2009, p. 479
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It has recently come to my attention that, independent from my investigations in [1], Professor K.D. Stroyan [2] obtains for a Tychonoff space X and a normal base β a quotient space on *X which is homeomorphic to the Wallman-Frink Hausdorff compactification w(X, β). Consequently, if X is Tychonoff, then Corollary 4.1 in [1] implies that Stroyan's space is homeomorphic to the space w(X, β)S which is constructed in Theorem 4.1 in [1]. Stroyan's result is obtained by use of a monadic closure operator.
I regret not mentioning Professor Stroyan's result in my paper [1].

Bulletin of the Australian Mathematical Society