Pretreatment of Starch-Free Sugar Palm Trunk (Arenga pinnata) to Enhance Saccharification in Bioethanol ProductionKusmiyati, Duwi Maryanto, Ringga Sonifa, Sabda Aji Kurniawan and H. HadiyantoMATEC Web Conf., 156 (2018) 01003DOI: https://doi.org/10.1051/matecconf/201815601003