Hironobu Takagi Shinya Kawanaka Masatomo Kobayashi Takashi Itoh Chieko Asakawa Social accessibility: achieving accessibility through collaborative metadata authoring. 193-200 2008 ASSETS http://doi.acm.org/10.1145/1414471.1414507 conf/assets/2008 db/conf/assets/assets2008.html#TakagiKKIA08