• Madalpingelised elektripaigaldised. Osa 8-1, Talitluslikud aspektid [Võrguteavik] : energiatõhusus = Low-voltage electrical installations. Part 8-1, Functional aspects : energy efficiency (IEC 60364-8-1:2019)2019 https://www.ester.ee/record=b5248920*est