@inproceedings{kratz2011capwidgets,
  author = {Sven Kratz and Tilo Westermann and Michael Rohs and Georg Essl}
  title = {CapWidgets: Tangible Widgets versus Multi-Touch Controls on Mobile Devices},
  booktitle = {Work in Progress, CHI 2011, Vancouver, Canada, May 7-12, 2011},
  year = {2011},
  month = may,
}