1. American Public Transportation Association. 2021a. “APTA - Ridership Trends.” 2021. https://transitapp.com/APTA.
2. American Public Transportation Association. 2021b. “The Impact of the COVID-19 Pandemic on Public Transit Funding Needs in the U.S.” American Public Transportation Association. https://www.apta.com/research-technical-resources/research-reports/the-impact-of-the-covid-19-pandemic-on-public-transit-funding-needs-in-the-u-s/.
3. Blumenberg E. A. and K. Shiki. 2003. “How Welfare Recipients Travel on Public Transit and Their Accessibility to Employment Outside Large Urban Centers ” July. https://escholarship.org/uc/item/04k2w2k7.
4. Brumbaugh S. 2018. “Travel Patterns of American Adults with Disabilities.” US Department of Transportation Bureau of Transportation Statistics. https://www.bts.gov/travel-patterns-with-disabilities.
5. City of Chicago. 2021. “Transportation Network Providers.” Chicago Data Portal. May 26 2021. https://data.cityofchicago.org/Transportation/Transportation-Network-Providers-Drivers/j6wf-834c.