@book { DieinnereFreiheit,
    title = "Die innere Freiheit",
    subtitle = "Das jüdische Element bei Viktor E. Frankl",
    author = "Risto {Nurmela}",
    year = "2001",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1091566"
}