@book { OptimumCurrencyAreasIsSouthernAfricareadytoformaMonetaryUnion,
    title = "Optimum Currency Areas: Is Southern Africa ready to form a Monetary Union?",
    author = "Christian {Sorgenfrei}",
    year = "2010",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842806863",
    url = "https://m.diplom.de/document/228147"
}