Arblaster, A. (2002) Democracy, 3rd Edition, Buckingham: Open University Press.
Birch, A. H. (2007) Concepts and Theories of Modern Democracy, 3rd Edition, Oxon: Routledge, Ch. 7 & 8. See also:
Dahl, R. (1989) Democracy and its Critics, New Haven Conn.: Yale University Press.
McKinnon, C. (2008) Issues in Political Theory, Oxford: OUP, Ch. 4.
Miller, D. (2003) Political Philosophy: A Very Short Introduction, Oxford: OUP, Ch. 3.