@book { DieExpressionismusdebatteunddieStudien,
    title = "Die Expressionismusdebatte und die «Studien»",
    subtitle = "Eine Untersuchung zu Brechts Sonettdichtung",
    author = " {Young-Jin Choi}",
    year = "1998",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1086839"
}