@article{DierckeDenker2019,
  author    = {Andrea Diercke and Carsten Denker},
  title     = {Chromospheric Synoptic Maps of Polar Crown Filaments},
  journal   = {Solar physics : a journal for solar and solar-stellar research and the study of solar terrestrial physics},
  volume    = {294},
  number    = {11},
  doi       = {10.1007/s11207-019-1538-z},
  year      = {2019},
}