During the celebration, participants will observe a minute of silence in tribute to the great number of journalists who have paid with their lives for our right to know.

UNESCO: World Press Freedom Day 2010

The number was retired in 1997 in tribute to Jackie Robinson, although players who had the number at the time were allowed to keep it.

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They adopted the name Google in early 1997, in a tribute to scale, a play on the number known as a googol--a one followed by a hundred zeros.

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It is an extraordinary record, although after picking up medal number 25 on Saturday Jackson paid tribute to his career-long coach Malcolm Arnold, who will hang-up his stop-watch when his athlete puts away his spikes.

BBC: Jackson confirms retirement plan

Federer, who is back at world number two following his semi-final win against Novak Djokovic, paid tribute to the champion.

BBC: Andy Murray beats Roger Federer to win Shanghai Masters

Supporters in the Nou Camp paid a special tribute to the 32-year-old Abidal in the 22nd minute of the match -- the same number as his squad shirt.

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For much of the 20th century, Mr Hirschfeld's drawings were there to be savoured in the Sunday edition of the New York Times, where one's appreciation of his gift for spearing a performer's physiognomy co-existed with a weekly hunt for the Ninas that is to say, the number of times Mr Hirschfeld had the name Nina embedded in almost every drawing, as a tribute to his only child.

ECONOMIST: London is the place to see Al Hirschfeld