Blum, Johannes, Stefan Funke, and Sabine Storandt. “Sublinear Search Spaces for Shortest Path Planning in Grid and Road Networks”. Proceedings of the AAAI Conference on Artificial Intelligence 32, no. 1 (April 26, 2018). Accessed October 25, 2021. https://ojs.aaai.org/index.php/AAAI/article/view/12075.