1. Reijnders H The sound level of a transformer in operation. Smit Transformatoren bv, Tech. Rep., October 1993 1 11
2. Power transformers Part 10: determination of sound levels, IEC 60076-10-:2001(E), May 2001
3. Patil S Investigation of transformer noise dependence of load, M.S. Thesis, Department of Electrical Engineering, Arizona State University, Tempe, AZ, December 2006
4. IEEE standard test code for liquid-immersed distribution, power, and regulating transformers, IEEE Standard C57.12.90-1999, June 1999