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@article{MZM_1992_51_2_a5, author = {A. M. Ivanov}, title = {Structure of ultrapowers on abelian groups over~$\omega$}, journal = {Matemati\v{c}eskie zametki}, pages = {40--45}, publisher = {mathdoc}, volume = {51}, number = {2}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1992_51_2_a5/} }
A. M. Ivanov. Structure of ultrapowers on abelian groups over~$\omega$. Matematičeskie zametki, Tome 51 (1992) no. 2, pp. 40-45. http://geodesic.mathdoc.fr/item/MZM_1992_51_2_a5/