Semiretracts--a counterexample and some results
نویسندگان
چکیده
In the paper (Theoret. Comput. Sci. 237 (2000)) Anderson present a theorem which characterizes any semiretract S by means of two retracts R and R!: The /rst part of the paper contains a counterexample for this characterization. Then some results are presented which /nally lead to the theorem which determines for a given semiretract S the minimal number of retracts R1; : : : ; Rm such that the equality S = ⋂m i=1 Ri holds. c © 2003 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 307 شماره
صفحات -
تاریخ انتشار 2003