@book { Introductionofblockchainintothecommoditytradingprocess,
    title = "Introduction of blockchain into the commodity trading process",
    author = "Christoph {Ulbig}",
    year = "2018",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/444591"
}