Gaya APA

BOYD, R, ., SILK, J, , , B, , . (2011). HOW HUMANS EVOLVED (ED 6). NEW YORK: THE ASIA FONDATION BOOKS FOR ASIA.

Gaya MLA

BOYD, ROBERT, ., SILK, JOAN, , , B., , . "HOW HUMANS EVOLVED". ED 6 NEW YORK: THE ASIA FONDATION BOOKS FOR ASIA, 2011. Text.