Historical clue formulations

• Poetic form featuring lexical repetition rather than rhyme — 2023-10-25
• Troubadour's six-stanza verse — 2006-01-31
• 39-line poem — 2001-04-15
• 39-line verse — 1999-03-20
• Verse form used by Dante — 1997-11-15
• Six-stanza poem — 1994-05-09