Mogilnykh, Ivan. “Completely Regular Codes in Johnson and Grassmann Graphs With Small Covering Radii”. The Electronic Journal of Combinatorics 29, no. 2 (June 17, 2022): P2.57. Accessed April 4, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v29i2p57.