Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MZ_1965__90_170463, author = {Gilbert Helmberg}, title = {\"Uber rein dissipative {Transformationen.}}, journal = {Mathematische Zeitschrift}, pages = {41--53}, publisher = {mathdoc}, volume = {90}, year = {1965}, zbl = {0178.38701}, url = {http://geodesic.mathdoc.fr/item/MZ_1965__90_170463/} }
Gilbert Helmberg. Über rein dissipative Transformationen.. Mathematische Zeitschrift, Tome 90 (1965), pp. 41-53. http://geodesic.mathdoc.fr/item/MZ_1965__90_170463/