Liu Xiao-Hui, Chen Mo-Han, Li Peng-Fei, Shen Yu, Ren Xin-Guo, Guo Guang-Can, He Li-Xin. Introduction to first-principles simulation package ABACUS based on systematically improvable atomic orbitalsJ. Acta Physica Sinica, 2015, 64(18): 187104. DOI: 10.7498/aps.64.187104