Zheldybayeva, B., Koshchanova, G., Amangosova, A., Dzhugembayeva, B., Turebayeva, G., Kasymkhanova, A., Syrbaeva, S., Kainbayeva, L., & Mukushev, B. (2026). Harmonic analysis of a periodic electrical signal using the Mathcad package. Recent Contributions to Physics, 96(1), 77-87. https://doi.org/10.26577/RCPh96120269