@article{EngelBoenischUllrichetal.2017,
  author    = {Andreas Engel and Harald B{\"o}nisch and Markus Ullrich and Robert Sitals and Olivier Membrive and Francois Danis and Cyril Crevoisier},
  title     = {Mean age of stratospheric air derived from AirCore observations},
  journal   = {Atmospheric chemistry and physics},
  volume    = {17},
  number    = {11},
  pages     = {6825 -- 6838},
  doi       = {10.5194/acp-17-6825-2017},
  year      = {2017},
}