Cita APA (7a ed.)

Singleton, D., & Ryan, L. (2004). Language acquisition: The age factor (2nd ed.). Multilingual Matters Ltd..

Cita Chicago Style (17a ed.)

Singleton, David, y Lisa Ryan. Language Acquisition: The Age Factor. 2nd ed. Clevedon: Multilingual Matters Ltd., 2004.

Cita MLA (9a ed.)

Singleton, David, y Lisa Ryan. Language Acquisition: The Age Factor. 2nd ed. Multilingual Matters Ltd., 2004.