A closed separable subspace of $\beta{\bf N}$ which is not a retract
نویسندگان
چکیده
منابع مشابه
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1987
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1987-0869226-5