Παραπομπή APA

Melzack, R. (1973). Puzzle of pain. Penguin Books.

Παραπομπή Chicago Style

Melzack, Ronald. Puzzle of Pain. Armondworth: Penguin Books, 1973.

Παραπομπή MLA

Melzack, Ronald. Puzzle of Pain. Penguin Books, 1973.