Cita APA (7th ed.)
Collins & Univesity of Birmingham. (1990). Collins COBUILD English grammar. Collins.
Cita Chicago (17th ed.)
Collins & Univesity of Birmingham. Collins COBUILD English Grammar. London: Collins, 1990.
Cita MLA (9th ed.)
Collins & Univesity of Birmingham. Collins COBUILD English Grammar. Collins, 1990.
Atenció: Aquestes cites poden no estar 100% correctes.