Cita APA (7a ed.)

Freud, S. (1974). Introductory lectures on psychoanalysis. Penguin Books.

Cita Chicago Style (17a ed.)

Freud, Sigmund. Introductory Lectures on Psychoanalysis. Gran Bretaña: Penguin Books, 1974.

Cita MLA (8a ed.)

Freud, Sigmund. Introductory Lectures on Psychoanalysis. Penguin Books, 1974.