Strode, Georgianna, John Derek Morgan, Benjamin Thornton, Victor Mesev, Evan Rau, Sean Shortes, and Nathan Johnson. “Operationalizing Trumbo’s Principles of Bivariate Choropleth Map Design”. Cartographic Perspectives, no. 94 (January 11, 2020): 5–24. Accessed November 23, 2024. https://cartographicperspectives.org/index.php/journal/article/view/1538.