@article{GDZPPN002429578, title = {All Knot Groups Are Metric.}, journal = {Mathematische Zeitschrift}, volume = {185}, year = {1984}, pages = {269-272}, zbl = {0536.57002}, url = {http://dml.mathdoc.fr/item/GDZPPN002429578} }
Clark, Bradd E.; Schneider, Victor P. All Knot Groups Are Metric.. Mathematische Zeitschrift, Tome 185 (1984) pp. 269-272. http://gdmltest.u-ga.fr/item/GDZPPN002429578/