@article{GDZPPN002539314,
title = {Secondary invariants for links},
journal = {Revista colombiana de matematicas},
volume = {6},
year = {1972},
pages = {106-115},
zbl = {0254.57011},
url = {http://dml.mathdoc.fr/item/GDZPPN002539314}
}
Gutiérrez, M. A. Secondary invariants for links. Revista colombiana de matematicas, Tome 6 (1972) pp. 106-115. http://gdmltest.u-ga.fr/item/GDZPPN002539314/