@article{10_1017_S0017089500004250,
     author = {Webb, J. R. L.},
     title = {On the homotopy property of degree for multivalued noncompact maps},
     journal = {Glasgow mathematical journal},
     pages = {125--130},
     year = {1980},
     volume = {21},
     number = {2},
     doi = {10.1017/S0017089500004250},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500004250/}
}