Intelligence in Services and Networks. Paving the Way for an Open Service Market 6th International Conference on Intelligence and Services in Networks, IS&N'99, Barcelona, Spain, April 27-29, 1999, Proceedings - Zuidweg, Han; Zuidweg, Han; Campolargo, Mario; Campolargo, Mario; Delgado, Jaime; Delgado, Jaime; Mullery, Al; Mullery, Al (Springer Berlin Heidelberg : Imprint: Springer, 1999)