@article{10_4153_CMB_1977_059_7,
     author = {Mura, R. Botto and Rhemtulla, A. H.},
     title = {Extensions of {Orderable} {Groups}},
     journal = {Canadian mathematical bulletin},
     pages = {393--395},
     year = {1977},
     volume = {20},
     number = {3},
     doi = {10.4153/CMB-1977-059-7},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1977-059-7/}
}