?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=September+2013&rft.title=An+Android-based+Intelligent+Tourism+Recommendation+System&rft.genre=proceeding