APA (7th ed.) Zitazioa
Leuffen, D., Rittberger, B., & Schimmelfennig, F. Integration and Differentiation in the European Union: Theory and Policies (2a edición.). Palgrave Macmillan.
Chicago Style (17th ed.) Zitazioa
Leuffen, Dirk, Berthold Rittberger, eta Frank Schimmelfennig. Integration and Differentiation in the European Union: Theory and Policies. 2a edición. Cham, Suiza: Palgrave Macmillan.
MLA (9th ed.) Zitazioa
Leuffen, Dirk, et al. Integration and Differentiation in the European Union: Theory and Policies. 2a edición. Palgrave Macmillan.
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