@article{MAN_1968__179_161778, author = {G. van DIJK}, title = {On {Symmetry} of {Group} {Algebras} of {Motion} {Groups.}}, journal = {Mathematische Annalen}, pages = {219--226}, publisher = {mathdoc}, volume = {179}, year = {1968}, zbl = {0167.14501}, url = {http://geodesic.mathdoc.fr/item/MAN_1968__179_161778/} }