Gaya APA

al., E. et al (2006). Cambridge Gramer Of English : A Comprehensive Guide Spoken And Writen English Gramer And Usage . New York: Cambridge University Press.

Gaya MLA

al., Et. et al. "Cambridge Gramer Of English : A Comprehensive Guide Spoken And Writen English Gramer And Usage". New York: Cambridge University Press, 2006. Text.