参考文献/References:
[1] 叶向东, 黄文, 邵松. 拓扑动力系统概论 [M]. 北京:科学出版社, 2008.
[2] HUANG W, LI S M, SHAO S. Null systems and sequence entropy pairs [J]. Ergodic Theory and Dynamical Systems, 2003(5):1505-1523.doi:10.1017/S0143385702001724.
[3] HUANG W. Tame systems and scrambled pairs under an Abelian group action [J]. Ergodic Theory and Dynamical Systems, 2006(5):1549-1567.doi:10.1017/S0143385706000198.
[4] HIRSCH M W, SMALE S, DEVANEY R L. Differential equations, dynamical systems, and an introduction to chaos [M]. 北京:人民邮电出版社, 2008.264-276.
[5] 尤承业. 基础拓扑学讲义 [M]. 北京:北京大学出版社, 1997.55-56.
[6] 熊金城. 点集拓扑讲义 [M]. 北京:高等教育出版社, 2003.62-63.