Gotham Baseball - The Wave
Home Run Apple Commemorates No. 31 Retirement - Mets History
Hall of Famer Mike Piazza has his No. 31 retired by Mets
Mets to Retire Mike Piazza's Number - WSJ
Piazza Gets Standing Ovation at Number Retirement - Mets History
On Mike Piazza & Dodgers retired numbers - True Blue LA
Not in Hall of Fame - The New York Mets Will Retire Mike Piazza's Number.
New York Mets to retire Mike Piazza's No. 31 on July 30 - ESPN - Mets Blog- ESPN
New York Mets: What Mike Piazza meant to the Amazins
Mets Retire Mike Piazza's Number With Uplifting Ceremony - Metsmerized Online