Murphy, R., & Altman, R. Grammar in use. Reference and practice for intermediate students of English.
Cita Chicago (17th ed.)Murphy, Raymond, i Roann Altman. Grammar in Use. Reference and Practice for Intermediate Students of English.
Cita MLA (8th ed.)Murphy, Raymond, i Roann Altman. Grammar in Use. Reference and Practice for Intermediate Students of English.
Atenció: Aquestes cites poden no estar 100% correctes.