APA (7th ed.) Citation

Wittgenstein, L. (1958). Preliminary studies for the "Philosophical investigations": Generally known as the Blue and Brown books ([2nd ed.].). Harper.

Chicago Style (17th ed.) Citation

Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": Generally Known as the Blue and Brown Books. [2nd ed.]. New York: Harper, 1958.

MLA (9th ed.) Citation

Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": Generally Known as the Blue and Brown Books. [2nd ed.]. Harper, 1958.