?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=Briquettes+production+as+teaching+aids+physics+for+improving+science+process+skills&rft.genre=article