@misc{10_4153_CMB_1991_013_4,
     title = {Units in {Group} {Rings} of the {Infinite} {Dihedral} {Group}},
     journal = {Canadian mathematical bulletin},
     pages = {83--89},
     year = {1991},
     volume = {34},
     number = {1},
     doi = {10.4153/CMB-1991-013-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1991-013-4/}
}