See Philip E. Converse, 'The nature of belief systems among mass publics', in D.A. Apter (ed.), Ideology and Discontent (New York: Free Press, 1964), p.
Voir Philip E. Converse, "The nature of belief systems among mass publics", dans D.A. Apter (dir.), Ideology and Discontent, Free Press, New York, 1964, p.