Van-Kien, Khanh-Linh Ha, Dai-Tan Tran, and Ngoc-Yen Hoang. 2023. “On the Second Hilbert Coefficients and Cohen-Macaulay Rings”. HPU2 Journal of Science: Natural Sciences and Technology 2 (2):3-10. https://doi.org/10.56764/hpu2.jos.2023.2.2.3-10.