Historical clue formulations

• Pair of boxers? — 2013-11-08
• Kennel outburst — 2011-02-23
• Reaction from one who has a bone to pick? — 2010-11-27
• Dog's bark — 2010-11-15
• Pound notes? — 2002-01-06
• Pound notes? — 1999-12-10