Gaya APA

Krashen, S, D., Terrell, T, D. (1988). The Natural Approach: Language Acquisition in The Classroom . United States of America: Prentice Hall.

Gaya MLA

Krashen, Stephen, D., Terrell, Tracy, D.. "The Natural Approach: Language Acquisition in The Classroom". United States of America: Prentice Hall, 1988. Text.