X. Zhang, X. Fan, W. Fan, and X. Zhou, “Study of Anionic Ring-Opening Polymerization and Macromolecular Structure Characterization for Poly(ethylene oxide)-poly(tetrahydrofuran)-poly(ethylene oxide) Triblock Copolymer”, ajc, vol. 26, no. 19, pp. 6391–6395, Sep. 2014.