8Hsieh H L,Yeh H C.Polymerization of butadiene and isoprenewith lanthanide catalysts:characterization and properties ofhomopolymers and copolymersRubber Chemistry and Tech-nology,1985.
10Gao Wei,Cui Dongmei.Highly cis-1,4 selective polymeriza-tion of dienes with homogeneous Ziegler-Natta catalysts basedon NCN-pincer rare earth metal dichloride precursorsJournal of the American Ceramic Society,2008.