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2. Metropolitan Transportation Authority. 2018. MTA Real-Time Data Feeds. Retrieved from https://api.mta.info/. Metropolitan Transportation Authority. 2018. MTA Real-Time Data Feeds. Retrieved from https://api.mta.info/.
3. Metropolitan Transportation Authority. 2018. Turnstile Data. Retrieved from http://web.mta.info/developers/turnstile.html. Metropolitan Transportation Authority. 2018. Turnstile Data. Retrieved from http://web.mta.info/developers/turnstile.html.
4. Planning for sustainable cities by estimating building occupancy with mobile phones
5. Michael R. Bloomberg. 2007. Inventory of New York City greenhouse gas emissions. New York City Mayor's Office of Operations Office of Long-term Planning and Sustainability. Retrieved from https://www1.nyc.gov/assets/sustainability/downloads/pdf/publications/NYC_GHG_Inventory_2013.pdf. Michael R. Bloomberg. 2007. Inventory of New York City greenhouse gas emissions. New York City Mayor's Office of Operations Office of Long-term Planning and Sustainability. Retrieved from https://www1.nyc.gov/assets/sustainability/downloads/pdf/publications/NYC_GHG_Inventory_2013.pdf.