Gaya APA

Swanson, C, P. et al (1980). World english 2 . New York: New York: Harcourt Brace Jovanovich; 1980..

Gaya MLA

Swanson, Carl, P.. et al. "World english 2". New York: New York: Harcourt Brace Jovanovich; 1980., 1980. Text.