@article{GDZPPN002319136,
title = {Conjugacy Relations in Subgroups of the Mapping Class Group and a Group-Theoretic Description of the Rochlin Invariant.},
journal = {Mathematische Annalen},
volume = {250},
year = {1980},
pages = {243-264},
zbl = {0409.57010},
url = {http://dml.mathdoc.fr/item/GDZPPN002319136}
}
Johnson, Dennis. Conjugacy Relations in Subgroups of the Mapping Class Group and a Group-Theoretic Description of the Rochlin Invariant.. Mathematische Annalen, Tome 250 (1980) pp. 243-264. http://gdmltest.u-ga.fr/item/GDZPPN002319136/