If McConnell tries to knock out a Democratic nominee tit-for-tat, Democrats won't accept a four-member commission, says Jim Manley, a spokesman for Senate Majority Leader Harry Reid of Nevada.

NPR: New FEC Nominees May Not Help McCain Campaign

When the plague reappeared in Britain and on the continent in the 1660s, European countries used tit-for-tat quarantines to keep out competitors, skim fees from merchants, reassure trading partners and punish those who quarantined them.

ECONOMIST: Where and when will the next pandemic emerge?

In April, Sudan and South Sudan slipped close to all-out war with a series of tit-for-tat air raids and ground attacks that prompted the African Union and Security Council to push the two sides to act.

CNN: Sudan and South Sudan sign partial agreement

As the match swung tit-for-tat, Leeds' Collins could have done better but was out-muscled by Burton as he stretched to reach a ball at the far post, only to smash his effort over the bar.

BBC: Sport - Football - Charlton 1-0 Leeds United

"Clearly some supporters feel aggrieved that a song they believe to be no more than a tit-for-tat 'wind up' of Celtic supporters should be singled out in this way and merit the attention of police, governments and anti-racism organisations, " said Bain.

BBC: Bain responds to 'Famine song'