Purnomo, Bagiyo Condro, and Noto Widodo. “Torque and Power Characteristics of Single Piston LPG-Fueled Engines on Variations of Ignition Timing”. Automotive Experiences, vol. 2, no. 1, Apr. 2019, pp. 22-27, https://doi.org/10.31603/ae.v2i1.2632.