The American who joined China's Communist Party
The American Sidney Rittenberg is one of only a handful of foreigners ever to join the Chinese Communist Party.
He went to China at the end of World War II with US forces - and stayed for 35 years. He knew Mao Zedong and saw China from the inside.
As the party celebrates its 90th anniversary, Rittenberg tells Michael Bristow why he joined the communists.