Institution: | 1. Department of Mathematics, Beijing Jiaotong University, Beijing 100044, PR China;2. Department of Mathematical Sciences, Tsing Hua University, Beijing 100084, PR China;3. School of Mathematics and Statistics, Yunnan University, Kunming, Yunnan 650091, PR China;4. Centre for the Mathematics of Symmetry and Computation, School of Mathematics and Statistics, The University of Western Australia, Crawley 6009 WA, Australia |