Abstract
In this paper, we prove that a space X is a g-metrizable space if and only if X is a weak-open, π and σ-image of a semi-metric space, if and only if X is a strong sequence-covering, quotient, π and mssc-image of a semi-metric space, where “semi-metric” can not be replaced by “metric”.
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This project was supported by NNSF of China (No. 10571151 and 10671173).
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Ge, Y., Lin, S. g-metrizable spaces and the images of semi-metric spaces. Czech Math J 57, 1141–1149 (2007). https://doi.org/10.1007/s10587-007-0117-x
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DOI: https://doi.org/10.1007/s10587-007-0117-x