Widerker, David (1995). «Libertarianism and Frankfurt's Attack on the Principle of Alternative Possibilities». Philosophical Review104 (2): 247-261. JSTOR2185979. doi:10.2307/2185979.
Fischer, Martin (1999). «Recent Work on Moral Responsibility». Ethics110: 93-139. doi:10.1086/233206.
Hunt, David (2005). «Moral Responsibility and Buffered Alternatives». Midwest Studies in Philosophy29: 126-145. doi:10.1111/j.1475-4975.2005.00109.x.
Widerker, David (1995). «Libertarianism and Frankfurt's Attack on the Principle of Alternative Possibilities». Philosophical Review104 (2): 247-261. JSTOR2185979. doi:10.2307/2185979.