@book { eLearningLernprozessundLernfortschrittskontrolle,
    title = "eLearning: Lernprozess und Lernfortschrittskontrolle",
    author = "Christoph {Lau}",
    year = "2003",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832468996",
    url = "https://m.diplom.de/document/222238"
}