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4. A.L.S. Corner, “Every countable reduced torsion-free ring is an endomorphism ring', Proc. London Math. Soc. (3), 13(1963), 687–710.
5. A.L.S. Corner, ‘On a conjecture of Pierce concerning direct decompositions of abelian groups', Proc. Coll. Ab. Groups, Tihany (Hungary) Sept. 1963, Akad. Kiadó, Budapest 1964.