On pureness in Abelian groups
M. A. Turmanov

References
1.	Mishina A. P., Skornyakov L. A., Abelevy gruppy i moduli, M., 1969
2.	Turmanov M. A., Endochistye podmoduli abelevykh grupp, Avtoreferat diss. $\dots$ kand. fiz.-mat. nauk, M., 1991
3.	Fuks L., Beskonechnye abelevy gruppy, T. 1, M., 1974; Т. 2, М., 1977
4.	Arnold D., Finite rank torsion-free Abelian groups and rings, Lecture Notes Math., 931, 1982
5.	Cohn P., “On the free product of associative rings, I”, Math. Z., 71 (1959), 380–398
6.	Reid J. D., “On the ring of quasi-endomorphisms of a torsion-free group”, Topics in Abelian Groups, Chicago, 1963, 51–68