Cita APA (7a ed.)

Roberts, R. (2008). Premium: B1 level. Coursebook (1st published.). Pearson-Longman.

Cita Chicago Style (17a ed.)

Roberts, Rachael. Premium: B1 Level. Coursebook. 1st published. Harlow: Pearson-Longman, 2008.

Cita MLA (9a ed.)

Roberts, Rachael. Premium: B1 Level. Coursebook. 1st published. Pearson-Longman, 2008.