I am willing to help you in finding journal articles where traffic congestion has been studied.
I am sending list of 5 and will send more in messages as 1500 words are max I can write here
I hope you will consider it.
1- Chang, Yu Sang, et al. “Is There More Traffic Congestion in Larger Cities? -Scaling Analysis of the 101 Largest U.S. Urban Centers.” Transport Policy, vol. 59, 2017, pp. 54–63.
2- Hopkins, John L, and McKay, Judith. “Investigating ‘Anywhere Working’ as a Mechanism for Alleviating Traffic Congestion in Smart Cities.” Technological Forecasting & Social Change, vol. 142, 2019, pp. 258–272.
3- Niu, Baozhuang, et al. “O2O Results in Traffic Congestion Reduction and Sustainability Improvement: Analysis of ‘Online-to-Store’ Channel and Uniform Pricing Strategy.” Transportation Research. Part E, Logistics and Transportation Review, vol. 122, 2019, pp. 481–505.
4- Bao, Yue, et al. “Investigation of the Traffic Congestion during Public Holiday and the Impact of the Toll-Exemption Policy.” Transportation Research. Part B: Methodological, vol. 104, 2017, pp. 58–81.