Citakan:SpringerEOM
Hazewinkel, Michiel, éd. (2001) [1994], "SpringerEOM", Encyclopedia of Mathematics, Springer Science+Business Media B.V. / Kluwer Academic Publishers, ISBN 978-1-55608-010-4
Hazewinkel, Michiel, éd. (2001) [1994], "SpringerEOM", Encyclopedia of Mathematics, Springer Science+Business Media B.V. / Kluwer Academic Publishers, ISBN 978-1-55608-010-4
