@inproceedings{tatsuo2013the,
title={The Spectrum of Strings on Warped AdS_3 x S^3},
author={Tatsuo Azeyanagi, Diego M. Hofman, Wei Song, and Andrew Strominger},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170228093714594204550},
booktitle={Journal of High Energy Physics},
volume={78},
pages={1304},
year={2013},
}

Tatsuo Azeyanagi, Diego M. Hofman, Wei Song, and Andrew Strominger. The Spectrum of Strings on Warped AdS_3 x S^3. 2013. Vol. 78. In Journal of High Energy Physics. pp.1304. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170228093714594204550.