Madalpingelised aparaadikoosted. Osa 1, Üldreeglid = Low-voltage switchgear and controlgear assemblies. Part 1, General rules (IEC 61439-1:2011)2012 https://www.ester.ee/record=b2860114*est

Toodete tehnilises dokumentatsioonis kasutatavate tingmärkide kujundamine. Osa 1, Põhireeglid = Design of graphical symbols for use in the technical documentation of products. Part 1, Basic rules (ISO 81714-1:2010)2011 https://www.ester.ee/record=b2715792*est