Wittgenstein, L. (1958). Preliminary studies for the "philosophical investigations": The blue and brown books. Harper.
Cita Chicago (17th ed.)Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. New York: Harper, 1958.
Cita MLA (9th ed.)Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. Harper, 1958.
Atenció: Aquestes cites poden no estar 100% correctes.