APA aipamena

Ferree, T. (2009). NorthStar 4: Listening and speaking (3.). Pearson Education.

Chicago Style aipamena

Ferree, Tess. NorthStar 4: Listening and Speaking. 3. San José, C.R.: Pearson Education, 2009.

MLA aipamena

Ferree, Tess. NorthStar 4: Listening and Speaking. 3. Pearson Education, 2009.