Historical clue formulations

• Murderer in P.D.Q. Bach's spoof opera "A Little Nightmare Music" — 2011-12-23
• Real-life opera composer who's a title character in a Rimsky-Korsakov opera — 2011-03-05
• Composer Antonio — 2010-10-07
• Composer who tutored Mozart's son — 2010-08-06
• Composer Antonio — 2009-05-14
• Composer of La Scala's premiere opera — 2000-11-12
• "Amadeus" role — 1998-06-14
• "Amadeus" antagonist — 1997-11-16
• Abraham's Oscar role — 1995-10-08
• Mozart's alleged poisoner — 1994-01-30