Doff, A., & Jones, C. (1997). Language in use: Upper-intermediate : self-study workbook with answer key (1st print.). Cambridge University Press.
Citação do estilo Chicago (17ª ed.)Doff, Adrian, e Christopher Jones. Language in Use: Upper-intermediate : Self-study Workbook with Answer Key. 1st print. Cambridge: Cambridge University Press, 1997.
Citação MLA (8ª ed.)Doff, Adrian, e Christopher Jones. Language in Use: Upper-intermediate : Self-study Workbook with Answer Key. 1st print. Cambridge University Press, 1997.
Nota: a formatação da citação pode não corresponder 100% ao definido pela respectiva norma.