Jürgen Steimle Nadir Weibel Simon Olberding Max Mühlhäuser James D. Hollan PLink: paper-based links for cross-media information spaces. 1969-1974 2011 CHI Extended Abstracts http://doi.acm.org/10.1145/1979742.1979885 conf/chi/2011a db/conf/chi/chi2011a.html#SteimleWOMH11