This is most authoritative because it's in English.

Sino-Vietnamese War (1979)
China:
6,954 dead, 14,800 injured

239 were prisoners of war
Vietnam:
Killed 42,000 people, injured 10,000 people, was captured more than 2,000 people, more than 50,000 civilian casualties
Sino-Vietnamese War（1984-----1989）
China:
Killed 939 people, injured 3,884 people
Vietnam:
Killed 11,700 people and injured 21,144 people, 61 prisoners