Gaya APA

BARNETT, R, A. et al (2000). PRECALCULUS, A Graohing Approach . united states of AMERICA: McGraw-Hill.

Gaya MLA

BARNETT, RAYMOND, A.. et al. "PRECALCULUS, A Graohing Approach". united states of AMERICA: McGraw-Hill, 2000. Text Book Mesin.