... most important of the many political parties are Congolese Labor Party or PCT [Denis SASSOU-NGUESSO, president]; Association for Democracy and Development or RDD [Joachim Yhombi OPANGO, president]; Association for Democracy and Social Progress or RDPS [Jean-Pierre Thystere TCHICAYA, president]; Congolese Movement for Democracy ... — The 1997 CIA World Factbook • United States. Central Intelligence Agency.