@article{1077472368,
author = {Whyburn, G. T.},
title = {Homotopy reductions of mappings into the circle},
journal = {Duke Math. J.},
volume = {11},
number = {1},
year = {1944},
pages = { 35-42},
language = {en},
url = {http://dml.mathdoc.fr/item/1077472368}
}
Whyburn, G. T. Homotopy reductions of mappings into the circle. Duke Math. J., Tome 11 (1944) no. 1, pp. 35-42. http://gdmltest.u-ga.fr/item/1077472368/