Do you need academic paper to prove that 1+1 = 2? There were serveral reasons for the VN war, and China was a part of it. In fact big powers, US, Soviet, France, China were all parts of it. Unlike Korea war in which both sides almost got wiped out before out before foreign forces came in, VN had already achieved strategical victory against French force and VN was capable of forcing France to withdraw its troops, by force. Then the US wanted to butt in, bringing along with them Soviet and China too. Then the Geneva accord was signed, which was officially to let the France withdraw in peace, and VN be independent as a whole. However, with the US, Soviet and China already there, what would be a simple unification voting session became a war between ideologies, a war between believes, a war among children of a big family. We have always blamed solely the US for this, but the truth is every nations that involved had some responsibilities. Be it good wills or ill wills, VN war broke out because of them.