@book { FoundationsofAgriculturalMarketAnalysisandAgriculturalPolicy,
    title = "Foundations of Agricultural Market Analysis and Agricultural Policy",
    author = "Ulrich {Koester}",
    year = "2020",
    publisher = "Vahlen",
    address = "München, Deutschland",
    url = "https://vahlen.openpublishing.com/document/1221375"
}