@article{AIF_1973__23_2_215_0,
     author = {Titus, Charles J.},
     title = {Extensions through codimension one to sense preserving mappings},
     journal = {Annales de l'Institut Fourier},
     pages = {215--227},
     publisher = {Institut Fourier},
     address = {Grenoble},
     volume = {23},
     number = {2},
     year = {1973},
     doi = {10.5802/aif.469},
     mrnumber = {50 #1265},
     zbl = {0267.57015},
     language = {en},
     url = {http://www.numdam.org/articles/10.5802/aif.469/}
}