@article{MAN_1980__249_163404,
     author = {Dennis Johnson},
     title = {Conjugacy {Relations} in {Subgroups} of the {Mapping} {Class} {Group} and a {Group-Theoretic} {Description} of the {Rochlin} {Invariant.}},
     journal = {Mathematische Annalen},
     pages = {243--264},
     publisher = {mathdoc},
     volume = {249},
     year = {1980},
     zbl = {0409.57010},
     url = {http://geodesic.mathdoc.fr/item/MAN_1980__249_163404/}
}