Elastic constants of NaBH4 and LiBH4: Instability of β-LiBH4Xiao-Dong Zhang, Zhu-Feng Hou, Zhen-Yi Jiang and Yu-Qing HouEPL, 88 3 (2009) 36005DOI: https://doi.org/10.1209/0295-5075/88/36005