Task: Question Answering
Input (English): Passage: Four battalions of rebel troops moved before dawn from the Mekong Delta towards Saigon, using armored personnel carriers and jeeps carrying machine guns. After cowing several police checkpoints on the edge of the capital with threats of machine-gun and artillery fire, the plotters put rebel sentries in their place to seal off Saigon from incoming or outgoing traffic. They then captured communication facilities in the capital, including the post office, to prevent messages from being sent in or out. As his troops took over the city, Phát sat in a civilian vehicle and placidly said "We'll be holding a press conference in town this afternoon at 4 p.m." He said "This is nothing to worry about. Just a little operation against some politicians." The rebels set up their command post in the Saigon home of General Duong Ngoc Lam, who had been removed from his post as Mayor of Saigon by Khánh. Lam had commanded the Civil Guard during Diệm's presidency and was one of his trusted supporters.The rebels took over the city without any gunfire, and used the national radio station to make a broadcast. Claiming to represent "The Council for the Liberation of the Nation", Phát proclaimed a regime change, and accused Khánh of promoting conflict within the nation's military and political leadership. He promised to capture Khánh and pursue a policy of increased anti-communism, with a stronger government and military. Phát said he would use the ideology and legacy of Diệm to lay the foundation for his new junta. Đức claimed the coup attempt was prompted by "the transfer to the capital of some neutralist elements, and by some pro-communists in the government". According to the historian George McTurnan Kahin, Phát's broadcast was "triumphant" and may have prompted senior officers who were neither part of the original conspiracy nor fully loyal to Khánh to conclude that Phát and Đức would not embrace them if they abandoned Khánh.In contrast to Phát's serene demeanor, his incoming troops prompted devotees at the Catholic cathedral—who were attending mass—to run away in fear. The Buddhists however, made no overt reaction to the pro-Diệm coup, even though the former president had pursued policies that discriminated against them. There was little reaction from most of the military commanders. The Republic of Vietnam Air Force commander Air Marshal Nguyễn Cao Kỳ had promised a fortnight earlier to use his aircraft against any coup attempt, but he took no action early in the morning. At the same time, Khiêm and Thieu's lack of public action was seen as implicit support for the coup, as their criticism of Khánh's leadership in junta meetings and private attempts to remove him were well-known. A US Embassy report to the State Department during the coup described Thieu and Khiêm as being "so passive that they appear to have been either tacitly supporting or associated with this move by Đức and Phát". 
Question: What is the full name of the person who commanded the Civil Guard during Diệm's presidency?
Output (English): Duong Ngoc Lam.