Littlejohn, A., & Hicks, D. (1998). Cambridge english for schools: Student's book four. Cambridge University Press.
Chicago-čujuhus (17. p.)Littlejohn, Andrew, juo Diana Hicks. Cambridge English for Schools: Student's Book Four. Cambridge: Cambridge University Press, 1998.
MLA-čujuhus (9. p.)Littlejohn, Andrew, juo Diana Hicks. Cambridge English for Schools: Student's Book Four. Cambridge University Press, 1998.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.