Lüdtke, A. (2012). History of concepts, new edition: Suitable for a better understanding of modern times? / Alf Lüdtke. Contributions to the history of concepts.
Lua i Stíl Chicago (17ú heag.)Lüdtke, Alf. "History of Concepts, New Edition: Suitable for a Better Understanding of Modern Times? / Alf Lüdtke." Contributions to the History of Concepts 2012.
Lua MLA (8ú heag.)Lüdtke, Alf. "History of Concepts, New Edition: Suitable for a Better Understanding of Modern Times? / Alf Lüdtke." Contributions to the History of Concepts, 2012.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.