The 2001 CIA World Factbook

by United States. Central Intelligence Agency

Comoros: noun: Comoran(s)

adjective: Comoran

Congo, Democratic Republic of the: noun: Congolese (singular and plural)

adjective: Congolese or Congo

Congo, Republic of the: noun: Congolese (singular and plural)

adjective: Congolese or Congo

Cook Islands: noun: Cook Islander(s)

adjective: Cook Islander

Costa Rica: noun: Costa Rican(s)

adjective: Costa Rican