Zheng, Lijuan, Bert van Wee, and Markus Oeser. “Combining Accessibilities for Different Activity Types: Methodology and Case Study”. Journal of Transport and Land Use 12, no. 1 (December 3, 2019): 853–872. Accessed March 28, 2024. https://jtlu.org/index.php/jtlu/article/view/1529.