Dellar, H., & Walkley, A. (2010). Upper intermediate outcomes: Student´s book. Heinle, Cengage Learning EMEA.

Dellar, Hugh, and Andrew Walkley. Upper Intermediate Outcomes: Student´s Book. Hampshire: Heinle, Cengage Learning EMEA, 2010.

Dellar, Hugh, and Andrew Walkley. Upper Intermediate Outcomes: Student´s Book. Heinle, Cengage Learning EMEA, 2010.