@article{10_4153_CMB_2015_071_0,
     author = {Beardon, Alan F.},
     title = {Non-discrete {Frieze} {Groups}},
     journal = {Canadian mathematical bulletin},
     pages = {234--243},
     year = {2016},
     volume = {59},
     number = {2},
     doi = {10.4153/CMB-2015-071-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-2015-071-0/}
}