The Mets should retire Mike Piazza's #31. Why haven't they? - Amazin' Avenue
COL@NYM: Mets celebrate Piazza with number retirement
It's great that the Mets are retiring Mike Piazza's number, but Gary Carter and Keith Hernandez deserve same honor – New York Daily News
Mets to retire Mike Piazza's No. 31 jersey this season – New York Daily News
Mike Piazza to have his Number Retired
Honoring Piazza? Paying Cespedes? Meet the Suddenly Generous Mets - The New York Times
Hall of Famer Mike Piazza has his No. 31 retired by Mets
Bruce's Journal: July 2016
Bruce's Journal: Mets Retire Mike Piazza's #31 in a Citifield Ceremony