Bibliography
Bell, J. M. 1973. “What is Referential Opacity?” The Journal of Philosophical Logic 2(1): 155–180.
Bell, J. M. and Mendus, Susan, eds. 1988. Philosophy and Medical Welfare. Royal Institute of Philosophy Lectures n. 23. Cambridge: Cambridge University Press.
Humberstone, I. Lloyd and Bell, J. M. 1977. “Two Systems of Presupposition Logic.” Notre Dame Journal of Formal Logic 18: 321–339.