Cita APA (7a ed.)

Kilbey, L. (2007). Challenges 3 cd-rom with workbook audio.

Cita Chicago Style (17a ed.)

Kilbey, Liz. Challenges 3 Cd-rom with Workbook Audio. Pearson Education, 2007.

Cita MLA (8a ed.)

Kilbey, Liz. Challenges 3 Cd-rom with Workbook Audio. 2007.