Error Note Chronicles: Inverted Overprint Errors

Error Note Chronicles: Mismatched Prefix Error

Error Note Chronicles: Obstructed Printing Errors

4 Most Popular Currency Misprints and How Much They Are Worth

Error Note Chronicles: Dual Denomination Error

The inverted overprint error frenzy, 40 years later

Error Note Chronicles: Stuck Digit Error

Error Note Chronicles: Printed Fold Error

Error Note Chronicles: Mismatched Serial Number Error

Clay Irving Collection - Error Notes