@book { CustomerRelationshipManagementCRMGrundlagenSystemeundAnwendungsgebiete, title = "Customer Relationship Management (CRM). Grundlagen, Systeme und Anwendungsgebiete", author = "Matthias {Dittrich}", year = "2005", publisher = "GRIN Verlag", address = "München, Germany", doi = "10.3239/9783638446860", url = "https://www.hausarbeiten.de/document/47829" }