@article{article8f3eed6f,
title   = {A survey on free subgroups in the group of units of group rings},
author = {Gonçalves, Jairo Zacarias and Del Río, Ángel},
year = {2013},
doi = {10.1142/S0219498813500047},
journal   = {Journal of Algebra and Its Applications}
}