?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Chang%2C+Victor&rft.aufirst=Victor&rft.aulast=Chang&rft.date=1+July+2020&rft.atitle=K-Clustering+Methods+for+Investigating+Social-Environmental+and+Natural-Environmental+Features+Based+on+Air+Quality+Index&rft.title=IT+Professional&rft.issue=4&rft.volume=22&rft.pages=28-34&rft.genre=article