36985
High concentrations of produced by disturbance of deep lake water saturated with are thought to have caused 37 fatalities at Lake Monoun , Cameroon in 1984 and 1700 casualties at Lake Nyos , Cameroon in 1986 .
 Lake Monoun, Cameroon, Lake Nyos, Cameroon
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Lake Monoun, Cameroon, Lake Nyos, Cameroon