@article{10_4153_CJM_1966_022_5,
     author = {Jr., Arthur H. Copeland},
     title = {Isotopy of {2-Dimensional} {Cones}},
     journal = {Canadian journal of mathematics},
     pages = {201--210},
     year = {1966},
     volume = {18},
     number = {1},
     doi = {10.4153/CJM-1966-022-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1966-022-5/}
}