@article{10_4064_fm_109_1_55_70,
     author = {Artur Solomon},
     title = {Homotopy 2-regular mappings whose inverses are open 3-cells},
     journal = {Fundamenta Mathematicae},
     pages = {55--70},
     publisher = {mathdoc},
     volume = {109},
     number = {1},
     year = {1980},
     doi = {10.4064/fm-109-1-55-70},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-109-1-55-70/}
}