Cita APA (7th ed.)

CHRISTOPHERSEN, P. (1969). An advanced english grammar. Macmillan.

Cita Chicago (17th ed.)

CHRISTOPHERSEN, Paul. An Advanced English Grammar. London: Macmillan, 1969.

Cita MLA (9th ed.)

CHRISTOPHERSEN, Paul. An Advanced English Grammar. Macmillan, 1969.