@article{10_4153_CMB_1981_074_5,
     author = {Ho, Chung-Wu},
     title = {When are {Immersions} {Diffeomorphisms?}},
     journal = {Canadian mathematical bulletin},
     pages = {491--492},
     year = {1981},
     volume = {24},
     number = {4},
     doi = {10.4153/CMB-1981-074-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1981-074-5/}
}