Cita APA (7a ed.)

Mangold, W. (1955). New active english (6a. ed.). Mangold.

Cita Chicago Style (17a ed.)

Mangold, Walter. New Active English. 6a. ed. Madrid: Mangold, 1955.

Cita MLA (9a ed.)

Mangold, Walter. New Active English. 6a. ed. Mangold, 1955.