Cita APA (7th ed.)

Wetz, B., & Pye, D. (2011). English plus: Student's book 4 (1a. ed.). Oxford University Press.

Cita Chicago (17th ed.)

Wetz, Ben, i Diana Pye. English Plus: Student's Book 4. 1a. ed. Oxford: Oxford University Press, 2011.

Cita MLA (9th ed.)

Wetz, Ben, i Diana Pye. English Plus: Student's Book 4. 1a. ed. Oxford University Press, 2011.