Historical clue formulations

• Beethoven's only opera — 2020-01-19
• Opera that includes the "Prisoners' Chorus" — 2009-09-18
• Opera that inspired the T-shirt slogan — 2004-02-25
• Vienna premiere of 1805 — 2000-08-27
• Opera subtitled "Wedded Love" — 1999-12-18
• Beethoven opera — 1999-06-10
• Beethoven's only opera — 1994-09-09
• Opera set in Seville — 1994-01-01
• Beethoven opera — 1993-12-23