@book { VonMusenundMusikZuOperLibrettoundSingspiel,
    title = "Von Musen und Musik: Zu Oper, Libretto und Singspiel ",
    author = "Hans-Albrecht {Koch}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b17663",
    url = "https://www.peterlang.com/document/1063349"
}