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By Xiaonan Wu, I-Liang Chern, You-lan Zhu, Zhi-zhong Sun. You-Lan Zhu is a Professor of Mathematics at the University of North Carolina at Charlotte. Xiaonan Wu is a Professor of Mathematics at Hong Kong Baptist University.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.