Nga, Pham Thi Thanh, and Nguyen Toan Thang. “Magnetic Order in Heisenberg Models on Non-Bravais Lattice: Popov-Fedotov Functional Method”. Communications in Physics 29, no. 2 (May 14, 2019): 119. Accessed November 29, 2021. https://vjs.ac.vn/index.php/cip/article/view/13508.