Cranston DW, Yu G. A New Lower Bound on the Density of Vertex Identifying Codes for the Infinite Hexagonal Grid. Electron. J. Combin. [Internet]. 2009Sep.18 [cited 2026May30];16(1):#R113. Available from: https://www.combinatorics.org/ojs/index.php/eljc/article/view/v16i1r113