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2. AASHTO, 2020. AASHTO Letter to Congress on COVID Phase 4. Technical Report American Association of State Highway and Transportation Officials. url: https://policy.transportation.org/wp-content/uploads/sites/59/2020/07/2020-07-20-AASHTO-Letter-to-Congress-on-COVID-19-Phase-4-FINAL.pdf.
3. What Do Americans Think About Federal Tax Options to Support Transportation? Results from Year Nine of a National Survey;Agrawal;Technical Report,2018
4. What Do Americans Think About Federal Tax Options to Support Transportation? Results from Year Eleven of a National Survey;Agrawal;Technical Report Mineta Transportation Institute,2020
5. AJC (2015). Poll of Georgia voters, January 2015. url: https://www.ajc.com/news/jan-2015-poll/.