?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Vu%2C+Thi+Hong+Nhan&rft.aulast=Vu&rft.aufirst=Thi+Hong+Nhan&rft.date=April+2012&rft.title=A+user+context+recognition+for+ubiquitous+computing+systems&rft.genre=proceeding