United Kingdom – CIA - The World Factbook

As the dominant industrial and maritime power of the 19th century, the United Kingdom of Great Britain and Ireland played a leading role in developing parliamentary democracy and in advancing literature and science. At its zenith, the British Empire stretched over one-fourth of the earth's surface. The first half of the 20th century saw the UK's strength seriously depleted in two World Wars and the Irish republic withdraw from the union. The second half witnessed the dismantling of the Empire and the UK rebuilding itself into a modern and prosperous European nation.

United States – CIA - The World Factbook

The US has the largest and most technologically powerful economy in the world, with a per capita GDP of $46,000. In this market-oriented economy, private individuals and business firms make most of the decisions, and the federal and state governments buy needed goods and services predominantly in the private marketplace.

Cidade global - Wikipédia

Uma tentativa de definir e categorizar cidades globais foi feita pelo Globalization and World Cities Study Group & Network (GaWC), baseado primariamente na Universidade de Loughborough, no Reino Unido. As cidades consideradas globais foram categorizadas no GaWC Research Bulletin 5, baseando-se em sua provisão de "serviços avançados de produção", tais como finanças, firmas de advocacia e publicidade.