Kenta Oku Shinsuke Nakajima Jun Miyazaki Shunsuke Uemura Hirokazu Kato A ranking method based on users' contexts for information recommendation. 289-295 2008 ICUIMC http://doi.acm.org/10.1145/1352793.1352855 conf/icuimc/2008 db/conf/icuimc/icuimc2008.html#OkuNMUK08