1. IEEE Std C57.91-2011: IEEE Guide for Loading Mineral-Oil-Immersed Transformers and Step-Voltage Regulators. Institute of Electrical and Electronics Engineers (2012). https://doi.org/10.1109/IEEESTD.2012.6166928
2. FIST 3-31: Transformer Diagnostics. United States Bureau of Reclamation (2003). https://www.usbr.gov/power/data/fist/fist3_31/fist3-31.pdf
3. IEC 60156:2018: Insulating liquids - Determination of the breakdown voltage at power frequency - Test method. International Electrotechnical Commission (2018)
4. IEC 60296:2012: Fluids for Electrotechnical Applications—Unused Mineral Insulating Oils for Transformers and Switchgears. International Electrotechnical Commission (2012)
5. SOU-N EE 20.302:2020: Standards testing of electrical equipment. National Power Company Ukrenergo, Kyiv, Ukraine (2020) (in Ukrainian)