?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Lubis&rft.au=Lubis%2C+Imran&rft.aufirst=Imran&rft.date=1990&rft.atitle=Etiologi+Infeksi+Saluran+Pernafasan+Akut+(ISPA)+dan+Faktor+Lingkungan&rft.genre=article