Gaya APA

HESTER, J. et al (2007). 21 St Century Astronomy (Ed. 2, Cet.1). New York: W.W.Norton And Company.

Gaya MLA

HESTER, Jeff. et al. "21 St Century Astronomy". Ed. 2, Cet.1 New York: W.W.Norton And Company, 2007. Text.