?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Fitria+Nugrahaeni%2C+Fitria&rft.aufirst=Fitria&rft.aulast=Fitria+Nugrahaeni&rft.title=IOP+Conference+Series%3A+Earth+and+Environmental+Science&rft.atitle=The+Effect+of+HPMC+Concentration+as+a+Gelling+Agent+on+Color+Stability+of+Copigmented+Blush+Gel+Extract+of+Purple+Sweet+(Ipomoea+Batatas+(L.)+Lam.)&rft.genre=article