@article{10_4153_CJM_1998_016_2,
     author = {Dokuchaev, Michael A. and Singer, Maria Lucia Sobral},
     title = {Units in {Group} {Rings} of {Free} {Products} of {Prime} {Cyclic} {Groups}},
     journal = {Canadian journal of mathematics},
     pages = {312--322},
     year = {1998},
     volume = {50},
     number = {2},
     doi = {10.4153/CJM-1998-016-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1998-016-2/}
}