Low-frequency cables and wires with p.v.c. insulation and p.v.c. Sheath - Part 2: Cables in pairs, triples, quads and quintuples for inside installations IEC 189-2 /  
 IEC 189-2 
ISO, IEC. 
 - 3rd edition. 
 - Geneva :   ISO :   IEC,   1981. 
 - 39 stron ;   30 cm.