@book { HarmonikundTonalitt,
    title = "Harmonik und Tonalität",
    subtitle = "Grundlagen einer neuen Musiktheorie",
    author = "Wilhelm Paul {Becker}",
    year = "2009",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1106813"
}