GOST 23862.11-1979 Rare-earth metals and their oxides. Chemical-spectral method of determination of impurities of vanadium, iron, cobalt, manganese, copper, nickel
GOST 23862.0-1979 Rare-earth metals and their oxides. General requirements for methods of analysis
GOST 23862.3-1979 Samarium, europium, gadolinium, terbium, holmium, erbium, thulium, ytterbium, lutecium and their oxides. Spectral method of determination of impurities in oxides of rare-earth elements
1979GOST 23862.11-1979 Rare-earth metals and their oxides. Chemical-spectral method of determination of impurities of vanadium, iron, cobalt, manganese, copper, nickel