@book { RollenundAufgabenineCommerceNetzwerken, title = "Rollen und Aufgaben in eCommerce Netzwerken", author = "Holger {Kahlert}", year = "2002", publisher = "Diplom.de", address = "Hamburg, Deutschland", doi = "10.3239/9783832462420", url = "https://m.diplom.de/document/221464" }