- Carl Icahn: Cigna’s merger with Express Scripts rivals ‘worst in corporate history’CNNMoney
- Icahn Warns Cigna Investors of Dangers in Exp-Scripts DealU.S. News & World Report
- Cigna ‘Dramatically Overpaying’ for Express Scripts, Icahn SaysBloomberg
- Analysts doubt Icahn can block Express Scripts dealSTLtoday.com