Rizal, Achmad, Riandini ., and Teni Tresnawati. 2018. “Premature Ventricular Contraction Classification Based on ECG Signal Using Multilevel Wavelet Entropy”. International Journal of Engineering & Technology 7 (4.44): 161-64. https://doi.org/10.14419/ijet.v7i4.44.26975.