EFISIENSI PROSES PEMBENTUKAN BIOGAS TERHADAP PENAMBAHAN EFFECTIVITAS MICROORGANISME 4 DENGAN BAHAN BAKU KOTORAN SAPI DAN SEKAM PADI MENGGUNAKAN ALAT BIODIGESTER (Efficiency of Process Biogas Formation against EFFECTIVENESS MICROORGANISM 4 with the addition of Raw Cow Manure and Rice Husk using Equipment Biodigester) - JATI, PUNDHI TRIONGGO (2015)