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2. IEC(2014).IEC 60076‐14:2014. Power transformers ‐ Part 14: Liquid‐immersed power transformers using high‐temperature insulation materials.
3. IEC(2010).IEC 60763 Specification for laminated pressboard.
4. IEC(2006).IEC 61061 Non‐impregnated densified laminated wood for electrical purposes.