@book { RohstoffealsalternativeAnlageklasse,
    title = "Rohstoffe als alternative Anlageklasse",
    author = "Sönke {Niefünd}",
    year = "2015",
    publisher = "BACHELOR + MASTER PUBLISHING",
    address = "Hamburg, Deutschland",
    url = "https://m.bachelor-master-publishing.de/document/309097"
}