What are the top ten philosophy books available?

According to the Guardian, the top 10 books are The Principles of Mathematics (Russell), Logic and Knowledge (Russell), Tractatus Logico (Wittgenstein), Philosophical Investigations (Wittgenstein), Remarks on the Foundations of Mathematics (Wittgenstein), Culture and Value (Wittgenstein), The Crisis of European Sciences and Transcendental Phenomenology (Husserl), The Bounds of Sense (Strawson), An Autobiography (Collingwood), and Metaphysics as a Guide to Morals (Murdoch).