@article{SF_1991__43_3_135098,
     author = {M. Gass},
     title = {The groups of the semigroup of compact subsets of a topological group.},
     journal = {Semigroup forum},
     pages = {83--92},
     publisher = {mathdoc},
     volume = {43},
     number = {3},
     year = {1991},
     zbl = {0726.22004},
     url = {http://geodesic.mathdoc.fr/item/SF_1991__43_3_135098/}
}