Shechan, A. (1972). Purnell's discovering nature. Purnell.
Chicago Edition CitationShechan, A. Purnell's Discovering Nature. London: Purnell, 1972.
Cita MLAShechan, A. Purnell's Discovering Nature. Purnell, 1972.
Atenció: Aquestes cites poden no estar 100% correctes.