9Bernhard A Wolf,Bernhard Will,Werner Obrecht,et al.Solution polymerization for the preparation of gel-free ethylene/vinyl acetate copolymers:US,4937303[P].1990-06-26.
10Hubert Sutter,Alois Kolwert,Werner Obrecht,et al.Process for the production of ethylene/vinyl acetate copolymers,new ethylene/vinyl acetate copolymers and their use:US,5089579[P].1992-02-18.