“ A New Multicarrier Sinusoidal Pulse Width Modulation (SPWM) Strategy Based on Rooted Tree Optimization (RTO) Algorithm for Reducing Total Harmonic Distortion (THD) of Switched-Capacitor Nine-Level Inverter in Grid-Connected PV Systems”. Indonesian Journal of Science and Technology, vol. 7, no. 1, Nov. 2023, pp. 19-36, https://ejournal.kjpupi.id/index.php/ijost/article/view/37.