@book { EvaluationdervirtuellenLernumgebungViBOS,
    title = "Evaluation der virtuellen Lernumgebung ViBOS",
    author = "Katharina {Beckenbach}",
    year = "2021",
    publisher = "Meidenbauer",
    address = ", Germany",
    url = "https://www.peterlang.com/document/1100482"
}