@book { CustomerRelationshipManagementimKonsumgterBereich,
    title = "Customer Relationship Management im Konsumgüter-Bereich",
    author = "Tim {Laubsch}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832446970",
    url = "https://m.diplom.de/document/220302"
}