@article{MAN_1972__196_162249,
     author = {Bjarne Toft},
     title = {On {Separating} {Sets} of {Edges} in {Contraction-Critical} {Graphs.}},
     journal = {Mathematische Annalen},
     pages = {129--147},
     publisher = {mathdoc},
     volume = {196},
     year = {1972},
     zbl = {0219.05059},
     url = {http://geodesic.mathdoc.fr/item/MAN_1972__196_162249/}
}