van den Brink, Martijn Ethics, Law and Politics, MPI for the Study of Religious and Ethnic Diversity, Max Planck Society;
https://www.cambridge.org/core/books/internal-market-and-the-future-of-european-integration/problem-with-market-citizenship-and-the-beauty-of-free-movement/7965CCF7CEB006C83FF6E73E3E45008B (全文テキスト(全般))