Gaya APA

al., E. et al (1995,1990,2005). Economics (Ed. Inter.,Ed. 9,Fourth). USA. By mcGraw-Hill, Inc.: -.

Gaya MLA

al., Et. et al. "Economics". Ed. Inter.,Ed. 9,Fourth USA. By mcGraw-Hill, Inc.: -, 1995,1990,2005. Text.