This was stopped only due to overproduction driving down the price and Communist officials other than Mao deciding that the practice was immoral .
According to Russian sources that the authors state they found , at the time the trade generated around $60 million a year for the Communists .
This was stopped only due to overproduction driving down the price and Communists officials other than Mao deciding that the practice was immoral .
According to Russian sources that the authors state they found , at the time the trade generated around $60 million a year for the Communists .