Tore Urnes Åsmund Weltzien Anne Zanussi Solveig Engbakk Julie Kleppen Rafn Pivots and structured play: stimulating creative user input in concept development. 187-196 2002 conf/nordichi/2002 NordiCHI http://doi.acm.org/10.1145/572020.572042 db/conf/nordichi/nordichi2002.html#UrnesWZER02