?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Haryadi&rft.aufirst=Rudi&rft.au=Haryadi%2C+Rudi&rft.title=JPCS&rft.atitle=The+use+of+augmented+reality+to+improve+mathematics+conceptual+understanding+of+pre-service+elementary+education+teachers&rft.genre=article