Yttrium, lanthanum, ytterbium, lutetium and their oxides. Chemical-spectral method of determination of impurities of vanadium, tungsten, iron, cobalt, manganese, copper, molybdenum, nickel, niobium, lead, tantalum, titanium and chromium
Residual current operated circuit-pressers with integral overcurrent protection for household and similar use. Part 1. General requirements and test methods