CrossRef
United States National Library of Medicine (US-NLM ID: 101744064)
China National Knowledge Infrastructure (CNKI)
Google Scholar
ROAD (Directory of Open Access Scholarly Resources)
CAS Source Index- A Division of American Chemical Society (CAS-SI, CODEN: JAPSJZ)
J-GATE PLUS
Research Bible (Academic Resource Index)
Geneva Foundation for Medical Education and Research (GFMER)
Directory of Research Journals Indexing (DRJI)
WorldCat
Index Copernicus (ICV)
Directory of Science
Journal TOCs
SCIENCEGATE
Scilit (an open-access database maintained by MDPI)