A method for efficiently estimating non-Gaussianity of continuous-variable quantum states Shao-Hua Xiang, Yu-Jing Zhao, Cheng Xiang, Wei Wen and Xue-Wen Long Eur. Phys. J. D, 74 1 (2020) 16 Published online: 28 January 2020 DOI: 10.1140/epjd/e2019-100421-6