@book { RatingChangeProbabilitiesAnEmpiricalAnalysisofSovereignRatings,
    title = "Rating Change Probabilities: An Empirical Analysis of Sovereign Ratings",
    author = "Alex {Bergen}",
    year = "2014",
    publisher = "Anchor Academic Publishing",
    address = "Hamburg, Germany",
    url = "https://m.anchor-publishing.com/document/287522"
}