Sources: Main sources: Thomas Brinkhoff: The Principal Agglomerations of the World, City Mayors.com
List Notes: Data updated by Top 5 of Anything: March 2010. Metro areas included in this list are: Toyko: Yokohama, Kawasaki & Saitama. Seoul: Bucheon, Goyang, Incheon, Seongnam & Suweon. Mexico: Nezahualcoyotl, Ecatepec & Naucalpan. Dehli: Faridabad & Ghaziabad. Mumbai: Bhiwandi, Kalyan, Thane & Ulhasnagar.