Zook, C., & Allen, J. (2002). Profit from the core: Growth strategy in an era of turbulence. The ChungRim Publishing.

Zook, Chris, and James Allen. Profit from the Core: Growth Strategy in an Era of Turbulence. Seoul: The ChungRim Publishing, 2002.

Zook, Chris, and James Allen. Profit from the Core: Growth Strategy in an Era of Turbulence. The ChungRim Publishing, 2002.