BOYD ROBERT & SILK B. JOAN. HOW HUMANS EVOLVED (1ST ED.).
Cita Chicago (17th ed.)BOYD ROBERT i SILK B. JOAN. HOW HUMANS EVOLVED. 1ST ED. NEW YORK,LONDON.
Cita MLA (9th ed.)BOYD ROBERT i SILK B. JOAN. HOW HUMANS EVOLVED. 1ST ED.
Atenció: Aquestes cites poden no estar 100% correctes.