@inproceedings{jozef1982every,
title={Every covering of a compact Riemann surface of genus greater than one carries a nontrivial$L$^{2}harmonic differential},
author={Jozef Dodziuk},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203301140501346},
booktitle={Acta Mathematica},
volume={152},
number={1},
pages={49-56},
year={1982},
}
Jozef Dodziuk. Every covering of a compact Riemann surface of genus greater than one carries a nontrivial$L$^{2}harmonic differential. 1982. Vol. 152. In Acta Mathematica. pp.49-56. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203301140501346.