Tuladhar, B. M., J. López-Bonilla, and O. Salas-Torres. “An Identity for Stirling Numbers of the Second Kind”. Kathmandu University Journal of Science, Engineering and Technology 13, no. 1 (October 4, 2018): 95–97. Accessed July 7, 2024. https://nepjol.info/index.php/KUSET/article/view/21266.