@article{700101,
     title = {A note on symmetries of invariant sets with compact group actions},
     booktitle = {Equadiff 8},
     series = {GDML\_Books},
     publisher = {Mathematical Institute, Slovak Academy of Sciences},
     address = {Bratislava},
     year = {1994},
     pages = {93-104},
     mrnumber = {MR1298458},
     zbl = {0813.58008},
     url = {http://dml.mathdoc.fr/item/700101}
}

Field, Michael; Golubitsky, Martin; Nicol, Matthew. A note on symmetries of invariant sets with compact group actions, dans Equadiff 8, GDML_Books,  (1994), pp. 93-104. http://gdmltest.u-ga.fr/item/700101/