Geulen, C. (2012). Reply: Christian Geulen. Contributions to the history of concepts.
Čikaški stil citiranja (17. izdanje)Geulen, Christian. "Reply: Christian Geulen." Contributions to the History of Concepts 2012.
MLA način citiranja (8. izdanje)Geulen, Christian. "Reply: Christian Geulen." Contributions to the History of Concepts, 2012.
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