How America Fought Chinese Troops in Vietnam War

This is a largely untold story of how Chinese intervention in Vietnam war played out. Why did US troops battle directly against Chinese special forces and advisors in the war? How did it happen? Exactly how much artillery, money and supplies did China send? A lot of people know about the Soviet Unions involvement in the Vietnam War in the 1960s and 1970s but not many people know about China’s role.