APA-ийн эшлэл(7 дахь хэвлэлт)

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

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

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

MLA -ийн эшлэл (9 дэх хэвлэлт)

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