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- Regions and Powers: The Structure of International Security, with Barry Buzan, (Cambridge University Press, 2003).
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- The Future of International Relations: Masters in the Making?, co-edited with Iver B. Neumann, (Routledge, 1997).
- European Integration and National Identity: The Challenge of the Nordic States, co-edited with Lene Hansen, (Routledge, 2001).
- International relations scholarship around the world, co-edited with Arlene B. Tickner, (Routledge, 2009).
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