Articles featuring or authored by Barrett Ersek:
Harvard Business Review: https://hbr.org/2015/07/break-your-industrys-bottlenecks
Strategic Discipline: http://strategicdiscipline.positioningsystems.com/bid/101713/Seven-Strata-of-Strategy-Step-Six-Establish-your-X-Factor
Growth Institute: http://www.rhythmsystems.com/blog/use-a-%E2%80%9Cthink-rhythm%E2%80%9D-to-find-your-x-factor
Entrepreneur Wiki: http://entrepreneurwiki.com/EW/Barrett_Ersek