@inproceedings{yang2013discontinuous,
title={Discontinuous Galerkin method for hyperbolic equations involving $\delta$-singularities: negative-order norm error estimates and applications},
author={Yang Yang, and Chi-Wang Shu},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20161012101417593673180},
booktitle={Numerische Mathematik},
volume={124},
pages={753-781},
year={2013},
}

Yang Yang, and Chi-Wang Shu. Discontinuous Galerkin method for hyperbolic equations involving $\delta$-singularities: negative-order norm error estimates and applications. 2013. Vol. 124. In Numerische Mathematik. pp.753-781. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20161012101417593673180.