Historical clue formulations

• Shipping container — 2025-11-07
• Padded envelope — 2025-11-05
• Certain padded container — 2024-05-31
• Padded envelope — 2017-03-30
• Post office purchase — 2013-04-12
• Post office item — 2009-04-05
• Many a circular — 2007-12-08
• "The Executioner's Song" author — 2000-02-06
• Padded envelope — 1998-11-15
• Handy postal container — 1996-07-29
• 1980 Pulitzer novelist — 1995-09-10