Bernal, J. D. (1969). Science in history. Penguin.
Chicago-čujuhus (17. p.)Bernal, John Desmond. Science in History. Harmondsworth: Penguin, 1969.
MLA-čujuhus (9. p.)Bernal, John Desmond. Science in History. Penguin, 1969.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.