1. Cox W.(2014 August 1).Urban cores core cities and principal cities.newgeography. Retrieved fromhttps://www.newgeography.com/content/004453-urban-cores-core-cities-and-principal-cities
2. Cox W.(2019 December 12).Distribution of transit work trips: urban core vs. suburbs and exurbs.newgeography. Retrieved fromhttp://www.newgeography.com/content/006495-distribution-transit-work-trips-urban-core-vs-suburbs-and-suburbs
3. Cox W.(2020 January 4).Population growth concentrated in auto oriented suburbs and metropolitan areas.newgeography. Retrieved fromhttp://www.newgeography.com/content/006527-population-growth-concentrated-auto-oriented-suburbs-and-metropolitan-areas
4. U.S. Energy Information Administration. (2020a June 23).Electric Power Annual 2018.
5. U.S. Energy Information Administration. (2020b January 8).Today in energy. Retrieved fromhttps://www.eia.gov/todayinenergy/detail.php?id=42435