1970IEEE/IEC 62032-2012 IEC 62032:2012(E)(IEEE Std C57.135-2011) Guide for the Application, Specification, and Testing of Phase-Shifting Transformers
1970IEEE/IEC 62032-2005 IEC 62032 Ed.1 (IEEE Std C57.135(TM)-2001): Guide for the Application, Specification and Testing of Phase-Shifting Transformers