@article{LudwigJesberg2015,
  author    = {Matthias Ludwig and Jens Jesberg},
  title     = {Using mobile technology to provide outdoor modelling tasks - the MathCityMap-Project},
  journal   = {Procedia : social and behavioral sciences},
  volume    = {191},
  pages     = {2776 -- 2781},
  doi       = {10.1016/j.sbspro.2015.04.517},
  year      = {2015},
}