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DOAB Directory of Open Access Books
2017
DOAB Directory of Open Access Books
2010
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2012
DOAB Directory of Open Access Books
2025
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2024
ScienceDirect
1987
DOAJ: Directory of Open Access Journals
2015-01-01 ~ 현재
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2017
Wiley Online Library Open Access
2014-01-01 ~ 2015-12-31