@book { SystemischesELearning,
    title = "Systemisches E-Learning",
    author = "Peter {Glanninger}",
    year = "2010",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-00121-1",
    url = "https://www.peterlang.com/document/1054180"
}