David Li, Hanan Samet, and Amitabh Varshney. (2021).<br/> Visualizing accessibility with choropleth maps. <br/>In <i>Proceedings of the 5th ACM SIGSPATIAL International Workshop on Location-based Recommendations, Geosocial Networks and Geoadvertising (LocalRec 21)</i>, Article9:1-4.<br/> DOI:10.1145/3486183.3492801