Putra, Theo Agytha. 2018. “Comparison Analysis of Quality of Ax-7 Advance Shelling Lubricants and Pertamina Enduro Racing Lubricants on Kawasaki Ninja 250cc Injeksi Motor”. Jurnal Teknik Mesin (Journal Of Mechanical Engineering) 7 (3). Jakarta, Indonesia:113-18. https://doi.org/10.22441/jtm.v7i3.4033.