Simplify the following text for a Grade 10 native English-speaking person.
Original: Also that September VÃ clav Havel , Dana NÄ mcovÃ and VÃ clav MalÃ 1\/2 , leaders of Czechoslovakia 's Velvet Revolution , published an open letter in The International Herald Tribune calling for the award to be given to Liu , while a petition began to circulate soon afterwards .
Simplified: In September 2010 VÃ clav Havel , Dana NÄ mcovÃ , and VÃ clav MalÃ 1\/2 published an open letter in The International Herald Tribune calling for the award to be given to Liu , while a petition began to circulate soon afterwards . All three had been leaders of Czechoslovakia 's Velvet Revolution .