@article{10_4153_CJM_1971_042_5,
     author = {Wong, H. Ship Fah},
     title = {The {Topological} {Degree} of {A-Proper} {Maps}},
     journal = {Canadian journal of mathematics},
     pages = {403--412},
     year = {1971},
     volume = {23},
     number = {3},
     doi = {10.4153/CJM-1971-042-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1971-042-5/}
}