@article{ComberMooneyPurvesetal.2016,
  author    = {Alexis Comber and Peter Mooney and Ross S. Purves and Duccio Rocchini and Ariane Walz},
  title     = {Crowdsourcing: It Matters Who the Crowd Are. The Impacts of between Group Variations in Recording Land Cover},
  journal   = {PLoS one},
  volume    = {11},
  doi       = {10.1371/journal.pone.0158329},
  year      = {2016},
}