@book { AnalysekonomischerModellemitMethodendesQualitativeReasoning,
    title = "Analyse ökonomischer Modelle mit Methoden des Qualitative Reasoning",
    author = "Christian {Steinmann}",
    year = "1999",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1087188"
}