1. Perspectives on Q., Hg. R. B. Barrett/R. F. Gibson, 1990.
2. On Q. New Essays, Hg. P. Leonardi/M. Santambrogio, 1995.
3. The Philosophy of W. V. Q., Hg. L. E. Hahn/P. A. Schilpp, 21998 [erw. Neuaufl.].
4. L. H. Nelson/I. Nelson: On Q., 2000.
5. Philosophy of Q., 5 Bde, Hg. D. Føllesdal, 2001.