@article{MZ_1972__125_171686,
     author = {Stewart E. Stonehewer},
     title = {Permutable {Subgroups} of {Infinite} {Groups.}},
     journal = {Mathematische Zeitschrift},
     pages = {1--16},
     publisher = {mathdoc},
     volume = {125},
     year = {1972},
     zbl = {0219.20021},
     url = {http://geodesic.mathdoc.fr/item/MZ_1972__125_171686/}
}