Zook, C. (2004). Beyond the Core: Expand Your Market without Abandoning Your Roots. Harvard Business Review Press.
Chicago-čujuhus (17. p.)Zook, Chris. Beyond the Core: Expand Your Market Without Abandoning Your Roots. Boston, Massachesutts: Harvard Business Review Press, 2004.
MLA-čujuhus (9. p.)Zook, Chris. Beyond the Core: Expand Your Market Without Abandoning Your Roots. Harvard Business Review Press, 2004.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.