@inproceedings{n.1990mean,
  title={Mean values of subtemperatures over level surfaces of Green functions},
  author={N. A. Watson},
  url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203537491341576},
  booktitle={Arkiv for Matematik},
  volume={30},
  number={1},
  pages={165-185},
  year={1990},
}
             
            
                
N. A. Watson. Mean values of subtemperatures over level surfaces of Green functions. 1990. Vol. 30. In Arkiv for Matematik. pp.165-185. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203537491341576.