The Effect of C/N Ratio and Type of Microbes Sludge to Biogas Production: Combination of Tapioca Industrial Wastewater and Tofu Industrial WastewaterAgus Hadiyarto, Danny Soetrisnanto, Faishal Miftahul Huda and Nimas Amelia IswaraMATEC Web Conf., 156 (2018) 03036DOI: https://doi.org/10.1051/matecconf/201815603036