Nietzsche, F. (1969). Thus spoke Zarathustra: : a book for everyone and no one. Penguin.
Cita Chicago (17th ed.)Nietzsche, Friedrich. Thus Spoke Zarathustra: : A Book for Everyone and No One. Harmondsworth: Penguin, 1969.
Cita MLA (9th ed.)Nietzsche, Friedrich. Thus Spoke Zarathustra: : A Book for Everyone and No One. Penguin, 1969.
Atenció: Aquestes cites poden no estar 100% correctes.