leinwand P. (2011). Essential Advantage. Harvard Bus.School Pub.
Chicago-čujuhus (17. p.)leinwand P. Essential Advantage. Boston: Harvard Bus.School Pub, 2011.
MLA-čujuhus (9. p.)leinwand P. Essential Advantage. Harvard Bus.School Pub, 2011.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.