MacCormick N., Questioning Sovereignty, Oxford University Press 1999.
Weiler J.H.H., The Constitution of Europe, Cambridge University Press, New York 1999.
Weiler J.H.H., The political and legal culture of European integration: An exploratory essay, „International Journal of Constitutional Law” 2011, t. 9, nr 3–4, s. 678–694, https://doi.org/10.1093/icon/mor054.