Crock J G.Separation and preconcentration of the rare-earth elements and yttrium from geological material by ion-exchange and sequential acidelution.Talanta,1986,33,601-606
[3]
Crock J G.Determination of rare-earth elements in geological materials by inductively coupled argon plasma atomic emission spectrometry.Ana.Chem,1982,54(8):1329-1333
[4]
Watkms P J.Determination of rare-earth elements,yttrium,scandium and hafnium using canon-exchange separation and inductively coupled plasma-atomic emission spectrometry.Chemical.Geology,1992,25(1/2):137-139.
[5]
Courtois C.Rare-earth elements and strontium isotope of polymetallic nodules from southeastern Pacific Ocean.Sedi mentology,1980,27(6):687-695.
[6]
Pattan J N.Rare earth elements distribution and behaviour in buried manganese nodules from the Central Indian Basin.Marine Geology,1993,112,305-312