Madalpingelised elektripaigaldised. Osa 4-442, Kaitseviisid. Madalpingepaigaldiste kaitse kõrgepingevõrkude maaühenduste tagajärjel ja madalpingevõrkude rikete tagajärjel tekkivate ajutiste liigpingete eest = Low-voltage electrical installations. Part 4-442, Protection for safety. Protection of low-voltage installations against temporary overvoltages due to earth faults in the high-voltage system and due to faults in the low voltage system (IEC 60364-4-44:2007 (Clause 442), modified)