@article{02218617,
title = {Extensions of racks and quandles.},
journal = {Homology, Homotopy and Applications},
volume = {7},
year = {2005},
pages = {151-167},
zbl = {1077.18010},
language = {en},
url = {http://dml.mathdoc.fr/item/02218617}
}
Jackson, Nicholas. Extensions of racks and quandles.. Homology, Homotopy and Applications, Tome 7 (2005) pp. 151-167. http://gdmltest.u-ga.fr/item/02218617/