Core Four - Wikipedia
Yankees' Andy Pettitte announces retirement - The San Diego Union-Tribune
A-Rod soaks in his farewell - The Boston Globe
Despite great career, don't expect Andy Pettitte to wind up in Cooperstown - Sports Illustrated
Andy Pettitte joins Yankees as advisor
Pettitte Leaves Behind a Core 3 - WSJ
Andy Pettitte to announce retirement, per report
Andy Pettitte to join Rivera in retirement – troyrecord
Pettite to attempt comeback with Yankees
Yankees' Andy Pettitte to Retire
Pettitte not retiring; Yanks, Astros in hunt