Metaphysics, a directory of websites

Aristotle’s Metaphysics, trans. by W. D. Ross

Wikipedia entry on metaphysics.

Metaphysics. Internet Encyclopedia of Philosophy

Heidegger, Martin

English translations of Heidegger’s works

Martin Heidegger. Wikipedia

Kant, Immanuel

Works by Immanuel Kant

Immanuel Kant. Wikipedia

Immanuel Kant. Encyclopedia Britannica

Immanuel Kant