Geulen, C. (2012). Reply: Christian Geulen. Contributions to the history of concepts.
Cita Chicago (17th ed.)Geulen, Christian. "Reply: Christian Geulen." Contributions to the History of Concepts 2012.
Cita MLA (8th ed.)Geulen, Christian. "Reply: Christian Geulen." Contributions to the History of Concepts, 2012.
Atenció: Aquestes cites poden no estar 100% correctes.