@book { LudwigErhardimSpiegelbayerischerSchulbcher,
    title = "Ludwig Erhard im Spiegel bayerischer Schulbücher",
    author = "Christine {Barthel}",
    year = "2008",
    publisher = "Meidenbauer",
    address = ", Germany",
    url = "https://www.peterlang.com/document/1104147"
}