Παραπομπή APA

BERNAL J.D. (1969). SCIENCE IN HISTORY. PENGUIN bOOKS.

Παραπομπή Chicago Style

BERNAL J.D. SCIENCE IN HISTORY. VICTORIA: PENGUIN bOOKS, 1969.

Παραπομπή MLA

BERNAL J.D. SCIENCE IN HISTORY. PENGUIN bOOKS, 1969.