?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Dinh%2C+Thi+Thai+Mai&rft.aulast=Dinh&rft.aufirst=Thi+Thai+Mai&rft.date=October+2019&rft.title=Smartphone+Indoor+Positioning+System+based+on+BLE+iBeacon+and+Reliable+region-based+position+correction+algorithm&rft.genre=proceeding