?url_ver=Z39.88-2004&rft_id=10.1109%2FICCISci.2012.6297189&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=L.E.&rft.aulast=Heng&rft.au=Heng%2C+L.E.&rft.isbn=9781467319386&rft.title=End+user's+perspective+of+usability+in+mobile+learning+system&rft.date=2012&rft.genre=proceeding