@article{GDZPPN002408937,
title = {Subgroups of Knot Groups.},
journal = {Mathematische Zeitschrift},
volume = {121},
year = {1971},
pages = {99-103},
zbl = {0222.55006},
url = {http://dml.mathdoc.fr/item/GDZPPN002408937}
}
Dey, I.M.S.; Cossey, J.; Meskin, S. Subgroups of Knot Groups.. Mathematische Zeitschrift, Tome 121 (1971) pp. 99-103. http://gdmltest.u-ga.fr/item/GDZPPN002408937/