WASET
    Khaled M. EL-Naggar,  Estimation of Load Impedance in Presence of Harmonics.   journal   = {International Journal of Electronics and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2009, vol. 26(2). 265 - 269
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/265.