Kaanel ka: Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. Equipment for testing, measuring or monitoring of protective measures. Part 9, Equipment for insulation fault location in IT systems (IEC 61557-9:2009). Osa teksti inglise k. Bibliogr. lk. 25. Avaldatud eesti keeles: mai 2010