Gregor Broll Markus Haarländer Massimo Paolucci Matthias Wagner Enrico Rukzio Albrecht Schmidt Collect&Drop: A Technique for Multi-Tag Interaction with Real World Objects and Information. 175-191 2008 AmI http://dx.doi.org/10.1007/978-3-540-89617-3_12 conf/ami/2008 db/conf/ami/ami2008.html#BrollHPWRS08