1. A. L. S.Corner, Every countable reduced torsion-free ring is an endomorphism ring,Proc. London Math. Soc. (3),13 (1963), 687–710.
2. A. L. S.Corner, Endomorphism rings of torsion-free abelian groups,Proceedings International Conference on the Theory of Groups, Australian National University, Canberra 1965 (Gordon and Breach, New York, 1967), 59–69.
3. N. T. Dáo Dissertation for the Degree of the Candidate of Math. Sci. Hung. Acad. Sci., Budapest (1989).
4. G.D'Este, A theorem on the endomorphism ring of reduced torsion-free abelian groups and some applications,Ann. Mat. Pura Appl.,116 (1979), 381–392.
5. L.Fuchs,Infinite Abelian Groups, Vol. I (1970), Vol II (1973), Academic Press, New York.