Cita APA (7a ed.)

Spencer, D. (1975). English for Proficiency (2nd ed.). Oxford University Press.

Cita Chicago Style (17a ed.)

Spencer, D.H. English for Proficiency. 2nd ed. Oxford: Oxford University Press, 1975.

Cita MLA (9a ed.)

Spencer, D.H. English for Proficiency. 2nd ed. Oxford University Press, 1975.