Coval Joshua. Williams, 2002. Harvard Business.
Chicago-čujuhus (17. p.)Coval Joshua. Williams, 2002. : Harvard Business.
MLA-čujuhus (9. p.)Coval Joshua. Williams, 2002. Harvard Business.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.