@Article{ 
  FerTio21,
  author = { Fernández-Real, Xavier and Tione, Riccardo },
  title = { Improved regularity of second derivatives for subharmonic functions },
  journal = { Proc. of the AMS },
  year = { 2021 },
  doi = { https://doi.org/10.1090/proc/16490 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/5291/ },
  note = { cvgmt preprint}
}