Cita APA (7th ed.)

Leech, G. e. a. (1977). A communicative grammar of english. Longman.

Cita Chicago (17th ed.)

Leech, Geoffrey et al. A Communicative Grammar of English. Londres, Inglaterra: Longman, 1977.

Cita MLA (9th ed.)

Leech, Geoffrey et al. A Communicative Grammar of English. Longman, 1977.