Cita APA (7th ed.)
Summers, D. (1997). LONGMAN essential activator: Put your ideas into words. Longman.
Cita Chicago (17th ed.)
Summers, Della. LONGMAN Essential Activator: Put Your Ideas into Words. England: Longman, 1997.
Cita MLA (9th ed.)
Summers, Della. LONGMAN Essential Activator: Put Your Ideas into Words. Longman, 1997.
Atenció: Aquestes cites poden no estar 100% correctes.