Reference 1: Per-capita income in USD PPP[14].
Reference 2: Norway, Sweden, Luxembourg, Denmark, Finland, United States, Canada, Australia, Netherlands, Germany, France, United Kingdom, Austria, New Zealand, South Korea, Japan, Belgium, Hong Kong, Slovenia, Ireland, Israel, Czech Republic, Kuwait, Singapore, Spain, Taiwan, Italy, Malta, Greece and Portugal.
Source: http://en.wikipedia.org/wiki/Developed_country
Reference 2: Norway, Sweden, Luxembourg, Denmark, Finland, United States, Canada, Australia, Netherlands, Germany, France, United Kingdom, Austria, New Zealand, South Korea, Japan, Belgium, Hong Kong, Slovenia, Ireland, Israel, Czech Republic, Kuwait, Singapore, Spain, Taiwan, Italy, Malta, Greece and Portugal.
Source: http://en.wikipedia.org/wiki/Developed_country
