Analysis on the feasibility of small-scale biogas from palm oil mill effluent (POME) – Study case: Palm oil mill in Riau-IndonesiaA P Nuryadi, A Raksodewanto A, H Susanto and Y PeryogaMATEC Web Conf., 260 (2019) 03004DOI: https://doi.org/10.1051/matecconf/201926003004