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https://hwb-eup2009.mpipriv.de/index.php/Rating-Agenturen (Any fulltext)
Leyens, P. C. (2009). Rating-Agentur. In J. Basedow, K. J. Hopt, & R. Zimmermann (Eds.), Handwörterbuch des Europäischen Privatrechts (pp. 1226-1230). Tübingen: Mohr Siebeck.