Cita APA (7th ed.)
Sawyer, W. W. (1955). Prelude to Mathematics (1a. ed.). Pelican books.
Cita Chicago (17th ed.)
Sawyer, W. W. Prelude to Mathematics. 1a. ed. Londres: Pelican books, 1955.
Cita MLA (9th ed.)
Sawyer, W. W. Prelude to Mathematics. 1a. ed. Pelican books, 1955.
Atenció: Aquestes cites poden no estar 100% correctes.