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2. The chemistry of the lanthanides;Moeller,1975
3. Lanthanide Probes in Life, Chemical and Earth Science. Theory and Practice;Bünzli,1989
4. Lanthanides and Actinides;Cotton,1991
5. S. Saez–Puche, P. Caro, Rare Earths, Editorial Complutense, Madrid, 1998.