A regular semi-metric space for which there is no semi-metric under which all spheres are open
نویسندگان
چکیده
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1961
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1961-0125562-9