Wetz, B., & Pye, D. (2011). English plus: Student's book 4 (1a. ed.). Oxford University Press.
Chicago-čujuhus (17. p.)Wetz, Ben, juo Diana Pye. English Plus: Student's Book 4. 1a. ed. Oxford: Oxford University Press, 2011.
MLA-čujuhus (9. p.)Wetz, Ben, juo Diana Pye. English Plus: Student's Book 4. 1a. ed. Oxford University Press, 2011.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.